“Venom”? More like cyanide.

The latest movie off the Marvel assembly line is a disaster on every level, from the hatchet-job writing to the horrid performances. Like so many recent superhero movies, ”Venom” has put its focus on juvenile humor instead of heart or action.

Tom Hardy plays Eddie Brock, the Guy Fieri of investigative journalists. Eddie is known for enthusiastically taking down powerful execs and politicians on cable TV, and he intends to do just that to Carlton Drake (Riz Ahmed), CEO of the Life Foundation.

He learns from an email on his lawyer girlfriend’s laptop that Drake’s company has been conducting deadly human experiments. So Eddie ambushes Drake and immediately gets fired from his TV network for unethical insubordination. His girlfriend Anne (Michelle Williams) rightly dumps him for spying on her inbox.

But Eddie quickly finds a new pal in Venom, an alien symbiote who latches onto him in Drake’s lab, where it’s being studied. Venom gives the shlub super-strength — and super-cannibalism. Yes, when the violent alien takes full control of Eddie’s body, he chows down on people’s heads.

Eddie and Flubber’s cousin go on a destructive rampage through San Francisco — with Venom lending an awkward commentary track — in an attempt to stop Drake’s evil scheme. And the movie ends. The abrupt climax is as lousy as the acting.

Hardy performs with a garbage disposal voice, mumbling rapidly in a scratchy whisper. He jumps around wildly like he’s just escaped a straitjacket. Director Ruben Fleischer may well have said, “Tom. Be crazy. Action!”

Fleischer also might have told Williams to be blander than tap water, because the Oscar nominee is doing little more than cashing a check here. Whether being romantic or in mortal peril, Williams’ face is identically blank. She and Hardy have the weirdest kissing scene I’ve ever seen.

Poor Ahmed, the best part of “Rogue One: A Star Wars Story,” is turned into a cartoon villain and handed lame dialogue like, “Bring me my creature!”

Nobody expects “Citizen Kane” when they walk into a superhero movie. But they also don’t expect an alien slug to call the main character a “pu–y” or to dish out relationship advice in a smooth Luther Vandross voice. The genuinely funny “Deadpool” movies have unleashed a slew of copycats trying to wring laughs out of hero stories. “Venom” gets laughs — the wrong kind.

If “Venom” seems like a rare miss for Marvel, that’s because it was made only “in association” with Marvel. It’s actually a Sony product that’s totally separate from the Marvel Cinematic Universe. That detached language, “in association with,” is used twice in the opening credits alone. My audience of film geeks was rolling with laughter, before any character had even spoken, at Marvel’s obvious attempt to distance itself from this wreck.