Milton Mamet is a scientist who serves as one of the Governor's right-hand men. He knew Phillip Blake before he became "The Governor", and is thus one of the Governor's longest lived pre/post-apocalyptic associates. Although allied with the Governor, Milton is taken aback by the Governor's violent methods. He (Milton) studies the decapitated bodies of Michonne's walker-pets and tests, with Andrea assisting, the possibility of communication with the residual human consciousness believed to still exist in the undead. To this end, he repeatedly asks emotionally significant questions to Mr. Michael Coleman, a voluntary test-subject dying of prostate cancer, in the hopes that after Coleman dies and reanimates, he may, despite his zombified state, initiate behavior which implies he understands and perhaps retains emotional reaction to the questions asked before death. He later helps Andrea escape to make peace with Rick, and accompanies The Governor to a peace summit, in which the Governor and Rick Grimes are to come to peaceful compromise between Woodbury and the Prison.
He expresses misgivings about The Governor's methods when he learns the Governor plans to kill everyone at the Prison save Michonne (whom he plans to brutally torture before death in retaliation for the loss of Penny and his eye). Milton commands Andrea to escape to the Prison to warn her old team about the Governor's plans and for the first time, takes a direct stand against the Governor by burning the captured walkers the Governor planned to use against the Prison group. The Governor realizes Milton revealed his plans to Andrea; this creates a final rift between Milton and the Governor. At the beginning of the Third Season finale, "Welcome to the Tombs", the Governor viciously beats Milton to a bloody pulp for this betrayal. Giving Milton a last chance to fall back into grace, he tasks Milton with the murder of a chair-bound Andrea (who made the escape to the Prison but was chased and captured by the Governor himself in the episode Prey), but Milton suddenly spins, knife in hand, to kill the Governor.
The attempt is futile and one-sided: the Governor seizes the knife and mortally wounds Milton with several hard thrusts to the abdomen. The Governor locks Milton in the torture chamber with Andrea, deciding to let the reanimated Milton eat her. When ordered by the Governor before the stabbing to pick up the torture impliments previously intended for Michonne, Milton surreptitiously leaves behind a pair of pliers behind the chair where Andrea sat, so that she could sweep them forward with her right foot, lift them with her toes, and use the pliers to remove the handcuffs binding her to the dentist chair. Milton orders Andrea to find a sharp tool to stab him in the head before he re-animates. As Milton sits dying against the wall, he asks Andrea why she came back to Woodbury after visiting her friends at the Prison and Andrea reveals her aborted assasination of the Governor as he slept. In the end, however, Andrea fails to free herself in time and a zombified Milton bites her before she permanently kills him. Rick's group, aided by Tyreese and Sasha, discovers the torture room, Milton's body, and a dying Andrea.
