TORONTO -- Vancouver actor-stuntman Rob Hayter has found himself at the centre of online buzz for playing a "Deadpool" character he admits he'd never heard of.

SPOILER ALERT: don't read any further if you don't want to know about Hayter's role late in the movie.

Hayter makes a brief cameo in the Marvel Comics superhero film as Bob, a mercenary who appears in a major fight sequence with antihero Deadpool, played by Ryan Reynolds. The film has surpassed US$491 million in global ticket sales and is on track to become one of the most successful R-rated movies of all-time.

Fans went into a frenzy on social media when the film was first released, proclaiming Bob to be a so-called Easter egg, which is an inside joke or hidden message slipped on screen.

That's because there's a character named Bob, Agent of Hydra -- a sidekick to Deadpool -- in the Marvel comic books.

But Bob's identity in the film is more ambiguous and Hydra isn't mentioned. Writers/producers Rhett Reese and Paul Wernick recently told that was 20th Century Fox's way of avoiding copyright infringement, since it doesn't have the rights to portray Hydra agents on screen (they belong to Marvel Studios).

Hayter admits he had no idea who Bob was and was "told nothing" when he was asked by "Deadpool" stunt co-ordinator Robert Alonzo to play "a small role" in the movie last summer in Vancouver.

"I didn't know who Bob from Hydra was when I walked on the set," says the 44-year-old stunt co-ordinator in a telephone interview from Vancouver.

"They didn't fill me in. I was just playing Bob, a mercenary soldier, in the movie, as far as I knew."

The Alberta native had to wear black fatigues with a balaclava. He and Reynolds had an improv session to help the writers establish dialogue between the two characters before shooting.

"Tim Miller, the director, came out and gave us some direction," says Hayter, whose long list of credits also includes the series "Unreal," "Mistresses" and "Lucifer."

"But basically we played it as a standard, straight-up acting scene between two friends and that's how we were told to play it."

In the scene, Deadpool knocks Bob over before recognizing him and calling out his name. Bob then pulls his balaclava down and they share some banter -- before Deadpool headbutts him and knocks him out.

It wasn't until Hayter got home after work that he learned about Bob from his 13-year-old son, who's a big graphic novel fan.

"I laughed, particularly after reading a couple of episodes of 'Deadpool,"' he says. "The more I read it, the more I liked it ... and now I'm kind of a 'Deadpool' fan."

He's also a big fan of Reynolds, noting "he's a consummate professional, he's kind and generous and funny and respectful."

"I can't say enough," says Hayter. "It was probably the most satisfying experience I've had on-set working with another actor."

Hayter says he's found the online Bob buzz to be "really engaging," and he'd love to play the character again, should he be asked.

"Films like this don't come around very often, roles like this don't come around very often, projects like this don't come around very often. It's fantastic to be a part of."