Larry Kaczynski

Larry Kaczynski was one of the UAC scientists in Doom 3, working in the Alpha Labs. He was one of the few personnel who survived the initial invasion of Hell.

During the demonic invasion, he gets trapped in a chamber when the power went out and asks the Marine to free him. The Marine is given either the choice of freeing him or activating the chamber with Kaczynski inside. If the Marine chooses to free him, Kaczynski can access to his lab next door, containing weapons, ammo, and Michael Abrams's PDA. He then locks his lab after the Marine leaves, thinking he will be safe.

If the player decides to activate the chamber instead, Kaczynski will be gruesomely killed and two Z-Secs will spawn. It is therefore in the player's best interest to help him.

His fate is ultimately unknown, but he most likely perished along with the rest of Mars Base, as Resurrection of Evil states the Marine was the only known survivor of Hell's invasion. However, The Lost Mission reveals that there was at least one other survivor, so it is possible that others may have survived, including Kaczynski.

The Player can kill Larry to get his PDA, which contains two emails, one of which is allegedly from an official from Nigeria asking for his help. This is a spoof of the Nigerian Email scams.