Some actors really delve into their roles, literally attempting to become a character both on and off the set. If the role is dark and disturbed, however, it can really take its toll.

We've all heard rumors of actors getting so deep in a role that they accidentally do things in-character or have trouble recovering after shooting a film. Most recently, many of these stories have emerged from the set of Suicide Squad, a film with a great number of dark, disturbed and villainous characters.

It's for this reason that a therapist is on set at all times for the Suicide Squad cast. If any of the actors feel like they're losing control, or that portraying their character is overwhelming, they have someone to talk to. So it makes sense that director David Ayer insists on a therapist being present in case an actor needs help.

Adam Beach, who portrays Slipknot in the film, explained the importance of the therapist to E! Online, noting that Ayer wants the characters in the film to appear real. Apparently, the director believes in this method acting, insisting on the actors tormenting themselves as their characters would.

"We kind of have like a therapist on board if you fall off the wagon and really are villainous," said Beach. "There's a friend of [Ayer's] that's very unique in making sure we have our ground."

Most particularly, Jared Leto – who portrays Joker in the film – has done a lot of disturbing Joker-like things, such as sending a rat to his co-star Margot Robbie and sending a dead hog to the rest of the cast. Photos of Leto on set show an actor so deep into his role that we cannot tell where the Joker ends and Leto begins.

Leto recently even refused to show up to events promoting the upcoming film, sending a video and letter to the cast as the Joker.

Of course, if Laurence Olivier – considered one of the greatest actors of the 20th century – were still alive, he'd probably take Leto by the hand and just tell him to act instead — as he once, at least according to acting legend, told Dustin Hoffman while filming Marathon Man.

In any case, it's good to know that Leto has someone to talk to if he gets carried away by the Joker.

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