Sid (Fallout 3)

Sid is an insane human captive in Vault 87 in 2277. He is trapped in Isolation Room 03.

Interactions with the player character
Sid turns hostile as soon as his cell is opened using the terminal or the emergency fire release, and will attack the player immediately if he sees them.

Effects of player actions
If you free Fawkes by activating the lab's emergency fire systems, this will open all the other isolation rooms, freeing both Sid and two centaurs. Although both are hostile towards you, they will also attack each other if they spot each other before spotting you, during which Sid most commonly dies. Although unlocking the door via terminal will result in Sid being hostile against player.

Notable quotes
If the door is unlocked by picking the lock, Sid is friendly but uncommunicative, screaming:
 * "No! It's all over me! I can feel it... it's invading my mind" (this is most probably the FEV he is screaming about).
 * "Get out of my head! Get the fuck out! Aaaaagh!"
 * "Can't you see?! They're all dead! It's all my fault!"

Appearances
Sid only appears in Fallout 3.

Behind the scenes

 * In the G.E.C.K., there are dialogue options explaining that he killed all of the people in his isolation room and was moved to another isolation room by super mutants.