A monster invasion is returning to Long Beach, and this year it could be the largest horde of ghouls, killers, zombies and horror fans the city has ever seen.

A record 50,000 people are expected to attend the annual Midsummer Scream Halloween and Horror Convention, which is taking over the Long Beach Convention & Entertainment Center starting today.

“I do not underestimate the spooky community. It’s not just people who love Halloween, horror and scary stuff. People love spooky, and our event has always been about covering all of that,” said David Markland, executive director and co-founder of Midsummer Scream.

Three-day general admission passes are sold out, but as of about a week before the horror convention, there were still a few single-day tickets and weekend VIP passes available. For those who attend it’s pretty much a macabre heaven of horror and a celebration of everything scary and frighteningly fun.

“There’s just so much going on,” he said. “We always aim to create a show where people come in and they leave but could only do half the stuff they wanted to and they come back all weekend. We love that.”

The celebration of all things horror will include a scary movie festival; panel discussions; and the always-packed marketplace, where people can get all sorts of horror-related goods like props, clothing and posters. There’s even a Black Cat Lounge where people can see and adopt cats, although not all are black felines.

One of the most popular activities at the convention has always been the Hall of Shadows, where people can walk through haunts created by professional and amateur creators. This year, film production company Lionsgate has created a maze dubbed “The Gears of Fear,” but don’t expect to know much about it until you get to Midsummer Scream.

“I am not allowed to say what it is. They want it to be a surprise for everybody, but it represents a bunch of different films from the Lionsgate library,” Markland said.

The Hall of Shadows also includes performances and photo ops. Horror short films will be on display at the Screaming Room, a screening room curated by Horrorbuzz, a horror review and news website.

Serious horror buffs always pack the various panels, which will include representatives discussing major attractions like Knott’s Scary Farm, Six Flags Magic Mountain’s Fright Fest, Queen Mary’s Dark Harbor, Castle Dark at Castle Park, the Winchester Mystery House and Thirteenth Floor Entertainment Group’s Haunted Hayride.

And the weekend is also infested with horror legends like Cassandra Peterson (aka Elvira, Mistress of the Dark); David Dastmalchian, star of “Late Night With the Devil”; and the “Candyman” himself, Tony Todd.

“We’ve really been overwhelmed by the response fans have had to Midsummer Scream and the way this event grows by leaps and bounds every year,” Markland said.