Theresa Chasar (Doom 3)

Theresa Chasar was one of the few female UAC employees in Doom 3. She is named after the sister of Tim Willits, the co-owner of id Software. She is also friends with Elizabeth McNeill. According to her PDA, she was involved in research with other UAC scientists on the Plasma gun.

During the Enpro level, the player can hear a female voice crying. Upon entering Theresa's office, she approaches him and pleads for help, but then a Lost Soul tears itself out of her head, ripping out her spinal cord, which then attacks the player.

Many more Lost Souls are encountered during the game, although this is the only time when one is seen to originate from a living human.