- "You saw it happen, that's how this started, right? It’s all happening right in front of your eyes, over and over again. Your body's here, but your mind is still there. There's a door and you want to go through it, to get away from it, so you do, and leads you right back to that moment. And you see that door again, you know it won't work but hell, maybe it'll work, so you step through that door and you're right back in that horrible moment every time. You still feel it every time, so you just want to stop opening that door, so you just sit in it. But I assure you, one of those doors leads out, my friend."
- —Eastman to Morgan Jones[src]
Although he only appeared in one episode, Eastman was shown to be a highly intelligent, caring and peaceful person who was a strong, determined survivor. Before the apocalypse occurred, Eastman suffered a terrible tragedy at the hands of one of his former patients, Crighton Dallas Wilton who murdered his whole family and thus turned Eastman bloodthirsty and into a vengeance seeker. Eastman was eventually able to achieve revenge against Winton by capturing him and starving him to death in a cell. Eastman appeared to regret this later on and it was from this incident that he vowed to never kill another human being again, a vow he maintained for the rest of his life. Although he seemed to be close to the edge on a few occasions after meeting Morgan. Despite his passive nature, Eastman was also a very capable fighter with his mastery of Akido and was easily able to fend off the dead and also Morgan in his crazed state. Eastman also seemed to show a degree of respect to the Walkers as after putting them down he would bury them in a homemade cemetery with grave markers reading their real names.
During the the time they knew each other, Eastman passed his wisdom and knowledge onto Morgan and effectively returned him from insanity and became an almost father figure to him. Eastman's care for Morgan was very apparent as he saved him from being attacked by one of Morgan's zombified victims, causing his own demise in the process.
Eastman was a forensic psychiatrist working for the prison system. He had a wife, son, and daughter who were all killed by one of his patients - Crighton Dallas Wilton, who escaped jail to take revenge on Eastman after failing an interview that would have granted him parole. Crighton surrendered to police shortly after but was given leniency despite his crimes - enraging Eastman.
A year later, Eastman kidnapped Crighton from prison and put him in a makeshift cell that he had built in his family's cabin; Crighton died 47 days later of starvation, and was later buried. When Eastman was returning to Atlanta to turn himself in, he discovered the apocalypse had already occurred. He then went back to his house to cut out a drawing that his daughter had done on one of the walls, losing his car on the way back and forcing him to return to the cabin on foot.
Since then he has survived by gardening, scavenging, and defending himself with Aikido (a martial art he learned prior to the apocalypse), while swearing to never kill another human being ever again. He also kept a goat named "Tabitha" for company and to help him make cheese, and maintained a sizable graveyard for every walker he has ever killed.
Eastman, hiding in the bushes, greets Morgan Jones as he arrives on his property, but after being shot at he manages to knock Morgan out with his staff, then places him in his cabin's cell. For the next few days he feeds Morgan and introduces himself, wanting to treat Morgan's PTSD and become friends; Eastman is planning a journey but needs someone to accompany him. He lets him out of the cell (which was unlocked the entire time - Eastman had long since thrown the key into the river) only to be attacked - breaking his daughter's wall drawing in the struggle. Eastman prevails and considers killing Morgan in revenge, but spares him instead.
The next morning he leaves Morgan to perform some errands, then returns to discover he had saved Tabitha from a pair of walkers. He thanks him and shows him a new staff he had crafted from one of Morgan's makeshift spears, and then proceeds to train him in the art of Aikido and the way of peacemaking. The two men bond over a long period, with Eastman revealing some of his backstory one night - involving Crighton and the cabin cell he built for him. While gathering some gear from one of Morgan's campsites and helping Morgan grieve for his own lost family, a walker approaches, but Morgan recognizes it and is too stunned to react; Eastman pushes him out of the way and is bitten, but manages to kill the walker. Morgan's mental state regresses and he attacks Eastman again, who subdues him and leaves him behind - taking the dead walker with him. He is next seen at the graveyard burying the same walker, when Morgan returns with another dead walker and Tabitha's corpse. Morgan then notices Crighton's grave and Eastman reveals more of his backstory - from Crighton's kidnapping and death, up until his discovery of the apocalypse.
Later inside the cabin, Eastman grows sicker from his bite wound and suggests that Morgan should leave - encouraging him to find other people to survive with. He then reveals that there is a gun in a lock box outside - implying that he is ready to die. Before they head outside, Eastman passes Morgan his daughter's rabbit foot - hoping that it will give him luck on his travels.
Upon seeing the undead 20's Man, Morgan has an episode of PTSD and freezes in place as Morgan had previously strangled him to death. Eastman rushes in to put down the walker before it can harm Morgan, stabbing him in the head with his staff but not before it bites him in the back. After a time, after telling Morgan that he (Eastman) is "ready," Eastman either commits suicide or is put down by Morgan before reanimation.
This list shows the victims Eastman has killed:
- Crighton Dallas Wilton (Caused)
- 20's Man (Zombified)
- Himself (Suicide) (Possibly)
- Tabitha (Negligently Caused)
- Numerous counts of zombies
- "Here's Not Here" (Flashback)
- His weapon of choice is a wooden staff.
- According to the marker Morgan makes for Eastman's grave, his first initial was the letter E.