Jonathan Ishii

"You don't know what I've seen! You can't possibly understand or comprehend!"

― Jonathan Ishii 

Jonathan Ishii
Rank	Scientist
Alignment	Friendly (until demonic conversion) Hostile (after conversion)
Fate	Zombie/Dead
Only appearance	Mars City Underground

Jonathan Ishii was a scientist who was part of the Delta Science Team. He disappears shortly before the demon invasion. The player's first assignment in Doom 3 is to find Ishii. Sergeant Kelly dispatches the player, following reports that Ishii was spotted in the Mars City Underground approaching the airlock that leads to the old communications array. Kelly instructs the player to bring Ishii back unharmed.

When the Player finds Ishii, the scientist panics and begs the Player to let him send a transmission to Earth warning them of Dr. Betruger's experiments. Ishii cryptically adds, "The Devil is real...I know, I built his cage."

Suddenly, the main portal in Delta Labs activates and demonic spirits come pouring out. Ishii is possessed by one of these demon spirits (as are many other humans throughout the base) and he becomes a zombie as a result. Ishii is the first enemy the player faces in the game.

Notes

• It is possible to kill Ishii before he is possessed.
• According to the book The Making of Doom 3, the original story had Ishii commit suicide by shooting himself in the head rather than become a zombie.
• The decrepit building at the end of the right half of the Blood Swamps in Doom Eternal is named "Ishii Castle" on the fast travel menu. As the left half is correspondingly called "Betruger Castle", this is seemingly a reference to Jonathan Ishii.