Once upon a time Bruce Willis was one of the biggest movie stars in the world, turning in memorable performances in movies such as “Die Hard” (1987), “Pulp Fiction” (1994), “The Sixth Sense” (1999) and “Unbreakable” (2000).

Now Willis is 62, and while he continues to find regular work (10 film credits over the last three years), he is no longer one of the biggest movie stars in the world — but he rarely if ever phones it in, even when the vehicle he’s driving is a low-rent knockoff.

“Once Upon a Time in Venice” is a cheerfully depraved guilty pleasure in which Willis and a host of other recognizable faces meander about, cracking off a few good lines here and there while the soundtrack blasts mood-setting tunes that all but announce the filmmakers didn’t have the budget to pay for REAL pop tunes.

At times it’s funny as hell. At other times it’s pretty much a disaster. But it never commits the crime of being tedious.

Willis plays Steve, a hardboiled private eye in Venice Beach who has a penchant for getting himself into trouble.

Example. At one point a couple of tough guys burst into Steve’s apartment and find him in bed with their sister, which leads to Steve jumping naked through the window and into a swimming pool, and then commandeering a skateboard (while still naked) to make his getaway.

I’m fairly certain a stunt double was used in some of the naked getaway scenes. I wasn’t interested in studying the screen all that closely to make sure.

Thomas Middleditch (“Silicon Valley”) plays Steve’s wannabe partner, who narrates the story.

Adam Goldberg plays “Lou the Jew” (nothing clever about that moniker), a landlord who wants to know who’s been spray-painting obscene messages on his apartment building.

Kal Penn and David Arquette, among others, make brief cameos that amount to nothing.

Jason Momoa plays a ruthless drug dealer with a bit of a dopey, semi-soft side.

John Goodman is a great fun as a surf shop owner.

Famke Janssen is Steve’s sister, Emily Robinson is Steve’s niece, and one or more dogs play their beloved Jack Russell terrier, who at one point is kidnapped, prompting Steve to risk everything to retrieve the dog.

Willis’ Steve is the common thread throughout — calmly negotiating for the return of his niece’s dog, impersonating a pizza delivery guy so he can infiltrate an enemy’s lair, lecturing a group of slack-jawed kids about the dangers of drugs and hookers, narrowly avoiding grievous bodily harm at every turn.

Of course Willis employs his trademark smirk and his familiar sarcastic line readings. Of course we’ve seen him play variations on this downtrodden, wisecracking cynic in better movies.

But B-movie Willis is still kind of a hoot.

★★★

RLJ Entertainment presents a film directed by Mark Cullen and written by Mark Cullen and Robb Cullen. No MPAA rating. Running time: 94 minutes. Opens Friday at AMC Loews Woodridge 18 and on demand.