The 'Superman' actor tells it like it is on his Letterman appearance.

Unearthed video footage of the late great Christopher Reeve is making the rounds on the internet today. The clip is from the 'Superman' actor's appearance on Letterman and he absolutely goes in on coworker and fellow actor, Marlon Brando.

Obviously when we hear the name Marlon Brando, we think the classics. 'The Godfather', 'Guys and Dolls', 'A Streetcar Named Desire.' The late actor apparently left a bitter taste in Reeve's mouth after working on 'Superman.'

According to Reeve, he wasn't fun to work with and it seemed like he had stopped caring about the craft. To be fair, that's a reasonable thing to be mad about as an actor.

David Letterman then pushes to see if Christopher had any fun working with Marlon, to which Christopher replies a vehement negative. It's refreshing to see an interview like this, because aside from the rare Ellen Degeneres debacle we don't get honesty much anymore.