They've never worked together on screen before and they're rarely photographed together so you'd be forgiven for not realising that Edward Norton and Leonardo DiCaprio are actually good friends. 

The pair met due to their mutual interest in protecting the environment and have gone many trips together around the world. Norton even has a nickname for DiCaprio that literally nobody else in the world would describe him as - "Unlucky Leo"

Birdman star Ed stopped by Jimmy Fallon last night and the host quizzed him about the time Norton saved the Oscar winner's life. The pair were on a diving trips in the Galápagos Islands and DiCaprio's fascination with technology got him into a sticky situation that could have ended very badly were it not for Norton.