Robert Downey Jr., Nicki Minaj, and More Celebrities Who’ve Insulted Their Costars

As much as we would love to pretend all our favorite celebs are besties in real life, the cold hard truth is that sometimes co-workers hate each other. Harrison Ford, Robert Downey Jr. and Nicki Minaj all had harsh things to say about their former costars — and they did not hold back!

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Click through the gallery to see which celebs exchanged the meanest insults with their costars.