"Help me."
― The last words of Theresa Chasar

Theresa M. Chasar (Identification Number: 0368-05) was a weapon analyst assigned to the EnPro facility on Mars, and was involved in research on the Plasma gun. She was friends with Dr. Elizabeth McNeil, and was one of the few female UAC employees. Being one of the few women on Mars, she was forced to put up with a considerable amount of unwanted flirting from her male co-workers, particularly her boss, Lloyd Renstrom. This had its advantages though, as her colleagues were always eager to assist her in her work.

When the player enters the Power Core Access area in Doom 3, a female voice can be heard crying. When the player reaches Theresa's office and enters it, she pleads for help before abruptly turning away with a demonic snarl. Before the player can do anything, however, a Lost Soul suddenly tears itself out of Theresa's head, ripping out her spinal cord, and attacks the player.

Many more Lost Souls are encountered during the game, although this is the only time one is seen to originate from a living human. How exactly the Lost Soul got to be inside of her in the first place is not known.

PDA Contents

Audio Logs

Weapon Research

This is the audio log of weapon analyst Theresa Chasar, dated November 3rd, 2145.

I am pleased to report that the preliminary tests on the ammo storage in the new Mach-3 Plasma Gun has far exceeded our expectations. We've realized a full 50% gain in the storage capacity of ammo packs as a result of utilizing techniques engineered in the Alpha Lab's molecular compactor. I believe with the ongoing compaction research, we will reach our goal of three times the plasma storage currently available in standard ammo packs. I would also like to mention that all of the employees here at the EnPro plant have been very helpful and quite eager to accommodate all of my requests. For security reasons, I've locked the plasma gun and the extra ammo in locker 063 with the door code 972.

End of log.


Plasma Storage Capacity (11-02-2145)

Please take a few minutes in the next day or so to create an audio report based on your plasma storage findings. The board is looking forward to hearing about your accomplishments.

As you know, security has been tight lately with all the accidents and as a result we can't be too careful. Please make sure you lock up your test weapon and add the cabinet code into your report.

Great Job,

Your Work (11-05-2145)

Hope you like your new office. I think you'll find it much easier to concentrate on the plasma gun project without those dweebs in engineering drooling all over you. How pathetic, right?

Anyway I'll be down there from time to time if you ever want to talk or get something to eat. You're probably sick of hearing it, but I think seeing you every day is more valuable to me than any amount of money I've gotten from working here. Believe me, being a supervisor I make a lot!

Your pal,

RE: Lloyd is driving me nuts! (11-10-2145)

I know what you're talking about, when I was still there I felt like I was the only woman surrounded by a bunch of drooling men. I miss the work but I don't miss that place, I feel like I'm lucky to be out of there.

Keep your eyes open for trouble; I don't trust some of the executives up there.

I can't wait to see you back on Earth when your research is completed.

Your Friend,

----Original Message----
Sent: 11-07-2145
To: Elizabeth McNeil

Lloyd has really outdone himself this time. He's moved me into the office next to the trench in Enpro. Does he really think by moving me to the most remote office on this wretched base that I'll be more attracted to him? might be working. Being isolated for this long is getting to me. I'm a chatter-box whenever I get the chance to talk to a real person.

Ok, I've got to get back to work.


  • Theresa is the only female human character to be seen in Doom 3.
  • Many players mistakenly believe that Theresa's head tears itself from her body and transforms into a Lost Soul (in part due to the Lost Soul's face having a vaguely female appearance). However, if one views the cutscene in slow motion, they will see that the Lost Soul actually bursts out of Theresa's head. Also, when gameplay resumes, if the player looks at her corpse closely, it's clear that her head, although badly destroyed, remains attached to her body. However, this could also be a gameplay/engine limitation.
  • Theresa is named after the sister of Tim Willits, the co-owner of id Software.

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