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Seven Psychopaths stars Christopher Walken, Colin Farrell and Sam Rockwell revealed that even with writer/director Martin McDonagh's brilliant vision, some of the most special moments happened completely by accident.

VIDEO: Seven Psychopaths and a Shih Tzu

The actors admitted that there was at least one scene that they couldn't get through without laughing, but instead of scrapping the footage for the blooper reel, McDonagh included their spontaneous and real reactions in the final cut.

"Sometimes it's those unexpected things that end up in the movie," said Walken.

Seven Psychopaths follows a screenwriter (Farrell) plagued with writer's block, who becomes entangled in a heist-gone-wrong when he follows his criminal friends (Walken and Rockwell) in search of creative inspiration.

"I think of myself in this ensemble as the, kind of, dad. I don't do anything bad to anybody do I," joked Walken, who plays a character that accidentally steals a Shih Tzu from a notorious gangster.

Despite the movie's title, the story does have heart to it. Rockwell explained that the film takes "poetic license" with the term psychopath, as many of the characters have at least "a little compassion."

"It's kind of about friendship and loyalty and forgiveness and loss and grief and guilt," said Farrell. "And then it's dressed up in a really entertaining, real extreme package."

Seven Psychopaths opens October 12.