Los Angeles ? It was once the stuff of bikers and rebels. It meant danger. Poison. Trouble ahead.

Now the skull-and-crossbones design more likely means “Pirates of the Caribbean” and a boatload of related merchandise.

With its third chapter of the blockbuster film franchise set to hit theaters Friday, Disney is unveiling pirate products from couture fashions to costume jewelry, plus toys, shoes, electronics, furniture and even “healthy pirate snacks for energy.”

Pirates have invaded pop culture.

“I think much of it can be attributed to this franchise really starting that whole trend again and making it so hot,” said Vince Klaseus, senior vice president of global marketing for Disney Consumer Products. “Now you see first-graders wearing it. Bikers are probably all (angry) about that.”

Three-time star Orlando Bloom noticed pirate style surface after the first film opened in 2003.

“That was what was phenomenal, when fashion started going like pirate-y and people were wearing T-shirts and hats and gear that had that rough-around-the-edges feel,” he said. “It really hit me on the first movie. But now because it’s been out there for so long, it just seems normal, which is really weird.”

The super-successful “Pirates” films can’t take all the credit, though. The skull-and-crossbones symbol and other seaworthy styles, such as headscarves and jangling jewels, have been popular for decades.

“Designers took the lead,” said New York-based marketing consultant Ryan Schinman, pointing to couturiers such as Alexander McQueen. “And Disney did a great job exploiting it.”

The studio’s kid-friendly films have had an effect on pirate style, Schinman noted, making the skull-and-crossbones symbol “a little lighter, a little magical and a lot more humorous than it used to be.”

“‘Pirates’ is not responsible at all for making it cool,” he said. “What it’s done is skewed the skull and crossbones younger.”

Johnny Depp’s pirate character, Captain Jack Sparrow, is someone kids can relate to, said toy consultant Chris Byrne: “He’s on the inept and silly side. He’s bad but he’s not all bad.”

Pirate-y trappings, particularly the skull-and-crossbones symbol, have been adopted by various groups since pirates disappeared in the 18th century, said historian Kevin Jones of the Fashion Institute of Design & Merchandising.

Back when tattoos were taboo, the skull and crossbones was a common, appropriately antisocial motif, he said. Bikers in the 1960s and ’70s sported the symbol to identify themselves as anti-establishment. Heavy-metal bands did the same thing in the 1980s, also adding scarves, rings and earrings. Skateboarders followed, then the Goths. As the skull-and-crossbones design became more popular, it lost its edge.

“I saw a skull-and-crossbones Hello Kitty,” Jones said. “When you see that, you know it has been totally divested of any of its toxic power. It’s simply become a fun, kitsch symbol.”

Professor Leo Braudy, a cultural historian at the University of Southern California, said pirates disappeared so long ago that they’ve become romanticized.

“There’s always that kind of nostalgia for those rebels of the past because they’re safe,” he said.

He noted that “Pirates of the Caribbean” isn’t the first film to anchor itself in pop culture. Everyone wanted to wear leather jackets and engineer boots after Marlon Brando sported them in the 1953 film “The Wild One.” Same with white T-shirts and blue jeans after 1955’s “Rebel Without a Cause.” And who can forget the torn sweat shirts and legwarmers popularized by the 1983 film “Flashdance”?