12 Monkeys TV Series Wiki

Dr. Cassandra Railly is a character on 12 Monkeys. She is a virologist while she worked for the CDC. After meeting a time traveler from the future, James Cole, she worked with him to help prevent the coming apocalypse. After being fatally injured, she was sent to the future where she was treated and became a time traveller along with the other members with Project Splinter. When meeting her mother when she went back in time, Cassandra went by Amelia Morrison.


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Cassandra Railly was a prominent virologist and physician who gave James Cole his mission to stop the Kalavirus. She was born on October 3, 1980, in Syracuse, New York. On April 12, 1986 she was admitted to a hospital and put into intensive care, with a diagnosis of viral meningitis; her symptoms included high fever, stiffness of the neck and vomiting. A sample of her cerebral-spinal fluid was sent to a laboratory.

As an adult, she earned a medical degree from Columbia University and became a doctor of medicine.



Railly traveled to 1944 from 2044 on a mission to prevent two of the Messengers from assassinating Thomas Crawford. At the Emerson Hotel, she met Cole, who had arrived two months prior, expressing amazement that he was enjoying himself in this era. They went to a party to find Crawford, where Railly pointedly chose to pose as Cole's sister, rather than his wife. She extracted Cole from an encounter with Robert Gale. After spotting Mantis with Crawford, she and Cole pursued them, but failed to prevent Crawford's murder. Afterwards, she and Cole had a harsh conversation, where she said she could not trust him any longer and reminded him that Aaron had died protecting her from him. They deduced that the Messengers were targeting Crawford's son, Tommy Jr., and found him at a mental institution. There they ran into the Messengers, and Railly killed the male Messenger. Mantis kidnapped Cole and used him as a human shield. Because of her concern for Cole, Railly was unable to shoot Mantis, despite Cole's urging. Railly spoke with Tommy, who referred to her cryptically as the one who aids "the traveler." She released him to Mantis in exchange for Cole. Although she and Cole tried to stop Mantis from killing Tommy, they were unsuccessful, and she was caught in a temporal paradox caused by Tommy's death. She was knocked unconscious and her tether to 2044 was severed, stranding her in 1944.

Railly and Cole were taken into custody by Gale and interrogated secretly. After Ramse rescued them, Railly favored immediately returning to 2044 to regroup, while Cole wanted to remain in 1944 to learn more about the Messengers. After Mantis escaped, Railly, Cole, and Ramse all splintered back to 2044.


Railly and Cole splintered to 1957 from 2044 in order to find the last Primary and prevent the Messengers from beginning the final paradox. Railly worked as a secretary at the factory where they believed the last Primary was located. After 11 months, during which Railly went on dates with various men who they suspected of being the Primary, neither she nor Cole had found any leads. Two days before the date of the final paradox, Railly learned that a new work crew would be brought in and suggested that Cole investigate. After Cole found a suspicious member of the work crew, Railly took a look at the man's employment file, finding a picture of a monkey on it. She and Cole concluded that this man was the Primary. However, this was a ruse prepared by Charlie, Cole's work friend who was a Messenger and who had fallen in love with and married his target, the last Primary. Railly confronted Charlie and his wife, but Charlie disarmed her and killed his wife with a knife carved from her own bone, triggering the final paradox. The explosion put Railly in a coma. Six months later, she woke up to find that Cole had abandoned her. She began working as a nurse, using her 21st-century medical knowledge to help her qualify as a physician in 1957. Eventually she tracked down Cole, who was hiding under an alias. She recognized the house where he was living, as the house made of cedar and pine, which she had seen in the Witness's visions. Cassandra realized that the Army of the 12 Monkeys had always planned for her and Cole to come here. She and Cole argued over why he abandoned her and what to do now that their mission had failed, and they confessed their feelings for each other and consummated their relationship.


Railly, Cole, and Ramse splintered in from 2044, having tricked Jones into sending them there. Railly and Ramse drugged and abandoned Cole, leaving him in order to look for Dr. Kirschner in East Berlin. They found Kirschner, but were captured and interrogated by Mossad agents who were also looking for Kirschner. Cole and Agent Gale rescued them from the Mossad agents, and Railly discovered that Kirschner was wearing an amulet with the sign of the 12 Monkeys. They escaped to Kirschner's laboratory in West Berlin, where they saw the young Olivia and the Word of the Witness. Mantis attacked in an attempt to kidnap Olivia, and Cole, Railly, and Ramse were all splintered back to 2044.


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In January, Railly made a presentation about preparedness a medical conference in Baltimore, Maryland. She was abducted but not harmed afterward by James Cole, who told her that the present was 2043, that she was living in the past and that a global plague would kill seven billion people in 2017. Cole said that he wanted Railly to tell him how to find Leland Frost. Railly denied knowing Frost. Cole took Railly into an unoccupied building and showed her a watch that looked identical to hers. Cole scratched the crystal on Railly's watch and an identical scratch appeared on the second watch. Cole told Railly to meet him in two years to the day at the John Adams Hotel in Baltimore and disappeared.


Railly went to Haiti to assist in containing a viral outbreak. Remembering the encounter with Cole, she assumed that the virus, which had not yet been identified, was much worse than it turned out to be. While in Haiti, Railly met Dr. Henri Toussaint, a native of Haiti who had returned to offer his services. She and Toussaint became intimate. One day, Toussaint left the clinic to acquire some medicine and never returned. Because of her statements about the seriousness of the disease, Railly was relieved of her duties and sent home; before leaving, she thought she sensed someone nearby while she was standing outside a tent. It was in January of this year, when Railly lost her practise.


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In January, James Cole returned, albeit several days late, and met with Railly at the John Adams Hotel, where she was waiting for him. He had the open bullet wound he suffered in 2013 and she nursed him back to health.

Railly took Cole to meet her friend Jeremy, who had discovered that "Leland Frost" referred to Leland Goines. She and Cole went to a party that Goines was scheduled to attend, where she encountered Aaron Marker and argued with him about the end of their relationship and her claims of Cole being a time traveler. After Cole tried to kill Goines, he and Railly were both abducted by Goines' men and interrogated.

After she learned about the Army of the 12 Monkeys from Goines, she asked Jeremy to look into them. When she visited him to learn what he had found, she came face-to-face with the Pallid Man, who had just killed Jeremy. She fled. Later, Aaron came to her bookstore, showing her photographs of Cole in North Korea in 2006 which contained the address of the J. D. Peoples Mental Hospital. She went there, posing as Cole's physician, and managed to free him. They confronted the Pallid Man, but he escaped with Jennifer Goines.

Railly and Cole tried to track down Henri Toussaint, only to discover from her ex-boss Jules that he had been killed in Haiti in 2014. In April 2015 or later, Railly was hired by the Centers for Disease Control and Prevention as a full-time specialist in viral containment; she took the job to learn more about the Night Room.

After she discovered the location of the Night Room, she and Cole tried to break in. They were captured by the Army of the 12 Monkeys, led by the Pallid Man. He revealed to her that Cole had killed Henri. Later, she demanded the truth from Cole and they talked about his past. Ultimately, Railly and Cole managed to activate the Night Room's safety mechanism, the "Big Burn", and destroy the original specimen of the plague virus, but the Pallid Man kidnapped her.

Railly was held by the Army of the 12 Monkeys and dosed with a hallucinogen. Olivia guided her through the hallucinations, taking her on a journey through the "red forest" and bringing her to meet the Witness. She saw him very briefly before Cole and Aaron managed to free her.

Railly and Cole went to a museum party to get information from an archaeologist on an ancient plate linked to the 12 Monkeys. While they were there, Railly taught Cole to dance. She interrogated the archaeologist and found that the plate was connected to the Druze religion and to Chechnya. Afterwards, she received a call from Cole, who was trying to stop Operation Troy using information he had gotten from her one week in her future. She and Aaron cooperated with the CIA to stop the release of the M5-10 virus. She said an emotional farewell to Cole, who apparently sacrificed himself to allow the CIA to destroy the virus via airstrike. The younger Cole later came to her to get the information on Operation Troy, and she sadly said goodbye for what she believed was the last time, knowing he was going to his death, but, as the older Cole had requested, did not tell him he was going to die in order to avoid changing the timeline.

Some time later, Railly traveled to the site of the airstrike in Chechnya to be sure Cole was erased from the timeline. She saw nothing at the site and concluded Cole was gone and the plague averted.

Railly and Aaron renewed their relationship, and were enjoying an intimate moment when Cole returned, shocking them both. She realized that Oliver Peters was the only possible remaining source of the plague virus, as both M5-10 and the remains had been destroyed. She and Cole went looking for Peters but found only his journal, which contained key information on the origin of the virus. Before Cole splintered away, Railly confronted him about the fact that time travel was killing him. Railly then persuaded Aaron to help her find Peters. She found Peters after he had recreated the M5-10 virus for the Army. He begged her to kill him, but she let him go. She and Aaron later discussed Peters' decision to make the virus to save his husband; Aaron suggested that protecting those closest to one was more important than billions of strangers, but Railly disagreed.

When a drunk Aaron suggested they give up trying to stop the plague, Railly refused and said they could not give up hope. Railly later returned to the bookstore to find a bloodied, injured Cole, who told her he knew the identity of the Witness.

Railly found the 2015 version of Jones, using the address she would give Cole in 2017, and convinced her to help cure Cole, who was dying from the effects of time travel. To prepare the cure, she and Jones went to find the Cole of 2015, who was a child, and met Cole's father, Matthew. Railly managed to convince Matthew to help them by mentioning the Army of the 12 Monkeys, and she prepared the cure. When the Army attacked the bookstore, Aaron attempted to take Railly to safety but she refused, hit him, and ran to help protect the Cole of 2015. After the Army was driven off, she and Cole said goodbye to Jones.

Railly and Cole interrogated Aaron for information on the Army. When Aaron escaped and was caught in a fire, Railly wanted to save him, but was dissuaded by Cole. She and Cole spoke with Jennifer Goines and learned that Ramse would be visiting Raritan National Laboratory. They broke into the laboratory, and confronted Ramse. A gunfight broke out when Railly shot Ramse, and Railly herself was shot. In order to save her, Cole used the time machine to send her to 2043, where Jones could treat her.


Having learned that Jennifer was responsible for unleashing the plague, Railly splintered in to New York from 2044, where she found Cole and Jennifer on a rooftop, at the mercy of a group of Army agents. She killed all of the agents and prepared to shoot Jennifer to stop her from releasing the plague virus. Cole shielded Jennifer with his own body and raised his own gun to stop Railly, causing a standoff.

After Jennifer decided not to release the plague, the standoff ended. Railly and Cole destroyed Jennifer's supply of the plague virus, altering history, although Railly retained memories of the previous timeline due to her being injected with the time-travel drug. Railly tried to kill Ramse, and when Cole objected, Railly sent Ramse back to 2044 and splintered, leaving Cole stranded in 2016. Later, when the Jennifer of 2044 forced Jones to rescue Cole, Railly was the one who retrieved Cole.

Railly returned to 2016 from 2044 in order to get the names of the Primaries from Jennifer. Upon meeting Jennifer, she was recognized by one of Jennifer's friends, who was an undercover operative of the Army, and she defeated the woman. She and Jennifer traveled to Jennifer's childhood home, where Jennifer started to become unstable due to traumatic memories of her youth. Cassie calmed Jennifer down, and Jennifer was able to tell her about another Primary, Kyle Slade. The Pallid Man arrived, and Railly threatened to kill Jennifer to keep the Army from sacrificing her like they had Tommy; however, the Pallid Man called her bluff and she was unable to do it. After being captured by the Army, Railly was forcibly administered another dose of the red hallucinogen by Olivia. In a vision, she again saw the Red Forest; this time she entered the house on the hill and saw Aaron's scarred face behind the Witness's mask. Jennifer roused her from her trance, and together they escaped the Army. Afterwards, Railly met Cole, who had splintered from 2044. She warned him that Slade was dangerous, and told him she had decided to stay in 2016 to take care of Jennifer.


Railly became the public face of the CDC while the plague was ravaging mankind. Cole saw her on television while he was still in Chechnya. Soon after, he was taken to an airport by a U.S. Army officer and returned to the United States. He was taken to the CDC facility in Baltimore, where he arrived just in time to speak briefly with a mortally ill Cassie.

Cassie and Cole are reunited.

She told him that they had been through a lot together in the two years since 2015, but she could not tell him what had happened because it would alter the timeline. She gave him a piece of paper with an address and told him to keep it on him at all times because it would save his life, before dying in his arms.


After being sent from 2015 by Cole, a wounded Railly arrived in 2043 at the Temporal Facility, surprising Jones.

Railly regained consciousness several days later, her injuries having been treated by Jones. She was imprisoned by Deacon, who was working with the Messengers. While being escorted to her cell, Railly diagnosed him with Wilson's disease and offered to treat it if he turned against the Messengers. He eventually agreed and freed her, pinning down the Messenger guarding the cell while Railly fatally stabbed him (her first kill). Railly would join him and his West VII reinforcements to restore control of the Temporal Facility to Jones.

Repairing the damage caused to the Machine would take 8 months, during which Railly would join Deacon and the other personnel on runs in the outside world, retrieving hardware and supplies. She became hardened by her experiences and Deacon's training to survive, becoming a skilled marksmen and fighter.

Eventually, Jones sends Railly back to 2016 to continue the mission, after her team determines that Jennifer Goines releases the plague in New York during the Chinese New Years celebration.


Railly splinters to the Chinese New Years celebration and, upon encountering Ramse (who she had last seen in 2015 when she shot him), knocks him out.

She tracks Jennifer to the rooftop where Cole and Jennifer are being held at gunpoint by 3 members of the Army. Cassie quickly takes them out, and her appearance is a huge surprise to Cole.

She intends to shoot Jennifer and prevent the plague, but Cole refuses, believing that he can convince Jennifer not to do it. Ramse shows up, adding to the tense standoff, with Railly in disbelief that Cole let him survive and is working with him. Jennifer eventually hands Cole the vial containing the virus and Railly stands down.

Railly says the next part of the mission is to destroy the remaining containers of virus on Jennifer's plane, and the group head to the hangar. They light the containers on fire, believing that this is the moment where they change history, and that their current selves will cease to exist. All three Travelers (Cole, Railly, and Ramse) experience painful distortions as time changes around them, but ultimately, they don't disappear as expected.

Railly suggests to Cole that they head back to 2044 to regroup and figure out what happens, and says she can't leave Jennifer and Ramse alive. Cole refuses to let her kill them and she expresses anger and disbelief that he's forgotten the mission. In the ensuing fight, Railly injects Ramse with the tether intended for Cole, so that Jones' team will be able to bring Ramse back and extract any information. Both Railly and Ramse are splintered back into the future.


Railly informs a surprised Jones that Cole has forsaken the mission. They imprison and torture Ramse for information regarding the Messengers and what their purpose was in using the Machine. Railly even goes so far as to bring Sam, Ramse's son, to his cell, and implying a threat to his safety, but Ramse is unable to give them any information.

Eventually, the Daughters sneak into the facility and kidnap Jones, and bring her to their Mother, Jennifer Goines. Jennifer reminds Jones of the message her 2016 self received from Cole, asking her to send someone back to him in Room 607 of the Emerson Hotel.


Jones sends Railly back to 2016 to retrieve Cole, who has also just stumbled on their only lead on the Messengers: a photo of Railly and Cole back in 1944 with a handwritten note, "Columbia University | September 1, 1944 | T.H. Crawford"



  • At the beginning of the show in 2015, she's 34 years old (which is a year older than Cole). In reality, Amanda Schull is two years younger than Aaron Stanford, who plays Cole.
  • She was born in Syracuse, New York.
  • She's the second main character (along with James Cole) to become a parent. José Ramse is the first.
  • Cassandra Railly used the name Amelia Morrison when she met her mother back in time. It should not be thought a coincidence that James Cole's fake name also includes the last name Morrison (Morris Morrison).
  • In the episode, Memory of Tomorrow, she hands Cole a Christmas card revealing her pregnancy. Inside, she has written:

You already gave me the best Christmas present.

Congratulations! You're going to be a father!

All my love,

- C.


At the beginning of the series, Railly is shown to be warm and caring, with a boundless respect for human life. She protests Cole's plan to simply kill Leland Goines, not able to support killing another human. Her optimism and belief that actions in the past do matter affects Cole, making him question his own morals and the impact of his actions on the people in the past.

The death of her boyfriend Aaron Marker has a profound effect on her, hardening her to the point of being able to shoot Ramse. After she is sent to 2043 and experiences the survival of the fittest life of the future, this ruthless streak becomes further embedded in her personality, with her becoming a skilled killer and fighter. She adopts a "do what needs to be done" mindset when it comes to her time travel missions, believing that both Jennifer and Ramse needed to be killed in the past to make certain the plague does not come to pass (despite Cole showing her that it wasn't necessary). She even is willing to threaten Ramse through his son, Sam, in order to get information.


Railly is a virologist and doctor at the top of her field. She's able to quickly and accurately diagnose and treat sicknesses, as demonstrated by her time in Haiti, treating wounds throughout the series.

After she is sent to 2043, she becomes a skilled marksman and fighter through Deacon's training and participating in scavenging runs outside the facility.

She's highly intelligent and is able to blend in with the time periods she's sent to (for example WWII era America) and infiltrate Spearhead in 2020.


Season 1
"Splinter" "Mentally Divergent" "Cassandra Complex" "Atari" "The Night Room"
"The Red Forest" "The Keys" "Yesterday" "Tomorrow" "Divine Move"
"Shonin" "Paradox" "Arms of Mine"
Season 2
"Year of the Monkey" "Primary" "One Hundred Years" "Emergence" "Bodies of Water"
"Immortal" "Meltdown" "Lullaby" "Hyena" "Fatherland"
"Resurrection" "Blood Washed Away" "Memory of Tomorrow"
Season 3
"Mother" "Guardians" "Enemy" "Brothers" "Causality"
"Nature" "Nurture" "Masks" "Thief" "Witness"
Season 4
"The End" "Ouroboros" "45 RPM" "Legacy" "After"
"Die Glocke" "Daughters" "Demons" "One Minute More" "The Beginning Part 1"
"The Beginning Part 2"