Gretchen Whistler is one of the medical staff present at Arkham Asylum during the events of Batman: Arkham Asylum. Despite only being seen briefly during the game (during Zsasz 's kidnap of Mike at the beginning of the game), her voice can be heard several times when listening to the patient interview tapes.
Her known patients include:
- Killer Croc
- Victor Zsasz (Transferred from Dr. Sarah Cassidy )
- The Riddler/Edward Nigma (Transferred from Dr. Penelope Young)
- Her voice is also heard during Harley Quinn's first interview tape, although she is simply introducing Harley as an intern at the Asylum, before her indoctrination with the Joker.
She displays much commitment to restoring the sanity to the inmates of Arkham, and is seemingly not intimidated by the fearsome Killer Croc, despite his best efforts to scare her.
She seems to be one of the most dedicated doctors at the asylum, understanding firmly just how dangerous and damaged the inmates within the asylum are, but also heavily focused on curing them. It is unknown if she survived the Joker's takeover, but as she was left in a secluded room with armed guards, it seems likely that she survived.
She is the only doctor at the asylum who, while interviewing various inmates, does not meet any sort of ill fate while her fellow coworkers were subjected to fear gas by Scarecrow, abducted by Victor Zsasz, put within a trance by Poison Ivy, or even outright tortured and murdered by Joker, during their employment at the facility.