He releases a feral mutant and kidnaps Imani, taking her to his basement laboratory where he removes one of her eyes to concoct a rejuvenation serum.
In the scuffle Vern shoots Schillinger while Carlos and the girls flee upstairs and hide in separate rooms.
Schillinger manages to trick Mengele into releasing him under the guise that he still holds Nazi sympathies and he uses this opportunity to free Imani.
The film ends with Albert preparing to battle several feral mutants released by a dying Mengele and a mid-credits scene shows Carlos waking up upstairs.
An after-credits scene shows Schillinger, Imani, and Carlos arriving to a new area, having all survived the previous horrors of the house.