Spoiler. End scene in the kitchen
So the dude was shot dead-turned into zombie by the alcoholic M.D., yet the end all is hunky dory as he & his gal talk of marriage & a dozen kids. Zombie dick=gross! And not biologically possible.
shareI don't think he was really dead. The doctor said something along the lines of "I'll show you how good a doctor I still am", and got his hidden medical tools. The implication is he was keeping these men down there, alive, not undead.
But the movie in general also doesn't make a ton of sense. There is no real explanation why an esteemed professor and psychologist would lead the despicable double life he's leading. He also early in the film seems to love his wife, yet later in a vague scene it almost seems as if he killed her, for no real reason. His motives are erratic and never really made clear, outside of some nonsense about "research".