Hilda Hidalgo was a mutated abomination created accidentally by an unwitting Umbrella Corporation scientist. She was once a terminally ill woman, the wife of cartel boss Javier Hidalgo and through his connections he was put in touch with Umbrella who were experimenting with a drug called T-JCCC203 which was based on the
t-Virus which could potentially cure fatal diseases (it's main designed function was to kill cancer cells).
While at first the operation appeared to be a success, the
t-Virus soon took hold of her and mutated her into an incredibly warped creature which resembled some kind of sea creature with large tendrils and a carapace. It's 'mouth' resembles a large, disfigured human hand (possibly the last remaining part of her true body). Instead of destroying the monster, her husband decided to keep her. Devastated at what Umbrella had done to his mother, he cut all ties with the company but still purchased B.O.W.s (Bio-Organic Weapons) based off Umbrella research (although on the black market, not directly from the company themselves) for his own purposes.
Interestingly, while her humanity was considered to be all but lost, there were moments where she appeared to remember her husband and her daughter (who is named Manuela Hidalgo) and would not attack them. While she does have a face (which appears to use portions of her original skull), it is covered with a hard shell, only revealing itself after mutating further. She also has a very large brain which seems to extend far behind her head - some of it is exposed through some parted tissue.
After she was released from her room and later killed, Javier decided to take the plunge himself and became a mutant abomination himself. Interestingly, Hilda appeared to cry at the moment of her death which is highly unexpected from a
t-Virus creature.
