Robert Downey Jr and Cillian Murphy mess around at awards show

Robert Downey Jr and Cillian Murphy are some pair of messers

Though the Irish man is known for being quiet and reserved it seemed that Robert was able to bring him out of his shell with his antics.

Robert decided he would stick a sign that read "no Irish jokes" onto Cillian's suit as he posed for photographers after his Desert Palm Achievement Award win for his lead role as J. Robert Oppenheimer.

The 'Iron Man' actor fully committed to the bit, even getting down on one knee to attach the piece of paper, making sure not to block the shot for the cameras.

The 58-year-old starred alongside Cillian in the flick, tackling the role of  Lewis Strauss.

Robert was the one to present the award to the Cork man and he had nothing but nice things to say about his colleague.

During his improvised speech, he said: "He is an anomaly. He’s been an actor’s actor for over 20 years and nobody dislikes this guy. That’s not easy.

"His character work and his onscreen intensity never fail. Captain captivating, it’s f*king titillating."

Robert added: "I’ve been in this game for 40-something years and I’ve never had the experience like watching Cillian carry the weight of J. Robert on his back for the whole time with his heart on his sleeve and all the required sophistication and restraint."

He also took a second to heap the praise onto the film's director Christopher Nolan calling him a "long game guy".

"It’s that kind of generational casting decision that gives you chills, just the potential of it… When I heard the announcement, I said, 'This is going to be an event cinema.' And then this guy had to prove it," he said.

Other winners on the night included Carey Mulligan for her performance in 'Maestro' and Poor Thing's Emma Stone.

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