Lady Gaga and Justin Bieber play aliens in new Men in Black movie

Lady Gaga and Justin Bieber will make out of this world cameos in the new Men In Black movie - as aliens.

The pop superstars are among the big name guest stars to make an appearance in the highly-anticipated third installment of the franchise, which reteams Will Smith and Tommy Lee Jones as secret agents in charge of policing extra-terrestrials.

Gaga and Bieber will play aliens who sit on a surveillance board, alongside kooky filmmaker Tim Burton.

Director Barry Sonnenfeld tells Collider.com, "In this (installment) there are a few people that you'll see up on the surveillance board including Lady Gaga, Tim Burton, who probably knows more about aliens than I do, and let's see who else... Justin Bieber."

They aren't the first superstar singers to appear in the series - Michael Jackson played Agent M in the second film in 2002.