Ad copy for Jess Franco’s twisted little horror film promises, “Nothing ever stripped your nerves screamingly raw like The Diabolical Dr. Z!” And that’s true, but mostly because my nerves have never been stripped before, screamingly raw, pan-fried or otherwise.
Presumably “Z” only to his pals, Dr. Zimmer (Antonio Jiménez Escribano, Frankenstein’s Bloody Terror) bides his time wearing Coke-bottle glasses and sticking syringes full of ungodly fluids into kitty cats. Some poor schmo stumbles to their door, so naturally Dr. Z takes him into the lab, shoves a needle through his head and makes the guy his slave.
Then, with his daughter, Irma (Mabel Karr, The Colossus of Rhodes), pushing his wheelchair, he crashes some sort of international cerebral summit, where Dr. Z tells his peers about his research. They don’t exactly scream “Diabolical!,” but they sure don’t cotton to it, either, enraging the good — I mean, diabolical — doctor to the point of a fatal heart attack.
Destined to carry on her father’s work, Irma goes to catch some dinner theater. She sees the brief show of Miss Death (Estella Blain), a young blonde in a see-through black leotard who performs a bizarre interpretive dance number on a floor painted to resemble a spider’s web. (Okay, so it’s not really a “dance” number, as she mostly shimmies across the floor on her tum-tum at a snail’s pace until she reaches Mortimer Snerd’s transvestite cousin. But this display of talent is met with voluminous, approving applause all the same.)
Irma, needless to say, is inspired, so she decides to fake her own death. What Miss Death’s performance had to do with this epiphany was lost on me, but face it: She’s creepy anyway. To me, the smile-free Irma looks like the lead singer of The Cardigans after being locked inside the freezer at KFC for a week.
To fake said death, Irma picks up a hitchhiker that resembles Irma only in that she is female. After stopping for a swim, Irma runs the girl over with the car. As she’s dousing the vehicle with gasoline from her neighborhood Mobil (who knew Franco was into product placement?), she gets burned herself, which causes her to acquire what looks like a guacamole beard. No problem — with the help of a mirror, she simply numbs her face and carves a scalpel into it.
With her death now faked, she poses as a Hollywood big shot to lure Miss Death into her clutches. The ruse works, as Miss Death is as dumb as rocks, and Irma uses her to do her dirty work, murdering the doctors who laughed at her father.
With lots of needle-stickin’ action, Dr. Z is a first-rate flick from Franco (Vampyros Lesbos), who has an eye for shot composition and a feel for ambience, yet rarely had good material. —Rod Lott
This is all you need to know to make an effective decision about whether to watch the giant cockroach film 
After 
