From Mel Gibson to Kevin Spacey, these cancelled stars made a comeback...

Mel Gibson saw his career plummet in 2006 after he made antisemitic comments when being arrested for driving under the influence, but in 2011, 'Oppenheimer' actor Robert Downey Jr. brought his pal out of the showbiz wilderness when he invited him to present him with the American Cinematheque Award.
Did you know these other cancelled stars made a comeback...