Entry for challenge. Using dawnbringer's palette.
"It took Lucy five years of research and a big laboratory accident to realize that what they were doing was wrong. On the last day of the job, lab assistant Lucy Skyburner decides to do the right thing and takes the tranquilizer gun to escape the burning underground facility. Cognition-challenged subjects shouldn't be used as experiments!"
Game references that come to mind: Flashback, Metroid, Blackthorne
EDIT: tweaked muzzle flash colors, added 'look-behind' animation before taking the needle from the suitcase.