Joaquin Phoenix laughs uncontrollably due to THIS reason

Joaquin Phoenix on the Beau Is Afraid set always laughed hysterically simply at the sight of his fellow actor Nathan Lane.

As per EW, the co-star Amy Ryan recalled that despite intense arguments on creative differences with the film's director Ari Aster, the Joker burst into laughter as soon he set eyes on Lane.

"He couldn't look at Nathan without laughing," adding, "And I don't mean giggling, I mean hysterically laughing. The cameras are getting ready, and sound is speeding, and Joaquin, he can't keep it together. I thought, oh my God, we're never going to get this scene done.

The actor continued, "But, in some inhumane nanosecond, it drops away, and he is in that character. So, from my experience working with him, my perspective, he's not one of those actors who needs to stay in this character for extended periods. He is so dialed-in that he can have this genuine, raucous, hilarious moment with Nathan and me and whoever else on set, and then, in a tenth of a second, he's in the scene."

Meanwhile, the film will hit theatres on April 21.