WARNING: The following contains spoilers for Hubie Halloween available now on Netflix

A hidden cameo in the Netflix horror-comedy, Hubie Halloween, teased an Adam Sandler crossover, which the actor isn't opposed to doing more of in the future.

In the opening sequence of Hubie Halloween, Ben Stiller reprised his role as Hal L. from Sandler's 1996 film, Happy Gilmore. Only this time, he traded his nursing home gig for a position at the psychiatric hospital. "He's a good friend of mine, I love him and our families are friends," Sandler told Yahoo Entertainment. "We talked about it and knew we'd have a good time doing that."

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Stiller hasn't been on the big screen since his role in the 2017 film, Brad's Status. In Hubie Halloween, he was joined by his daughter Elle Olivia Stiller, who played a coffee barista in the Netflix film. However, the more important aspect of Stiller's role is the fact that his character joined two Sandler universes together. If Hal L. exists in the same universe as Hubie Halloween, could there be more Sandlerverse crossovers in the future?

"I'd like that, I just gotta get mentally prepared for that," Sandler joked. "So that'll probably happen in another 35 years. We're gonna get to that."

Stiller's cameo isn't the only Easter egg spotted in Hubie Halloween. Many of Sandler's previous characters were brought back to reference the actor's past. The main character, Hubie Dubois, is a reference to Sandler's role as footballer Bobby Boucher in 1998's The Waterboy. Dubois' love interest, Violet Valentine, is also a nod to many of Sandler's past cinematic romances. Each one of Sandler's love interests, including Veronica Vaugn in 1995's Billy Madison, Virginia Venit in Happy Gilmore, Vicki Vallencourt in The Waterboy and Valerie Veran in 2000's Little Nicky, all have double-V initials.

There's also a red-headed bully in Hubie Halloween named Andy O'Doyle, who is most likely a descendant of the "O'Doyle Rules" family in Billy Madison. Fans can even spot flying bags of dog poop -- a signature move of Sandler's past characters.

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"It just happens that we run out of stuff to talk about so just bring that s**t back from 1961," Sandler said in reference to the Easter eggs.

Hubie Halloween follows the story of Hubie Dubois, a Halloween fanatic who simply wants the town to have a safe holiday. Although he's become the butt of the town's jokes, it's up to Hubie to save the town during a real-life murder investigation. As the Halloween Helper races to save Salem, fans are introduced to a number of cameos including Julie Bowen, Kevin James, Steve Buscemi, Ray Liotta, June Squibb, George Wallace, Shaquille O’Neal and many Saturday Night Live actors.

Starring Adam Sandler, Noah Schnapp, Paris Berelc, Julie Bowen, Karan Brar, Kevin James, Maya Rudolph, June Squibb, Steve Buscemi, Shaquille O’Neal and Ray Liotta, Hubie Halloween is streaming on Netflix.

Source: Yahoo Entertainment