Find the error: Of all the disasters that occured during the movie's production, the death of the two stars who performed their stunts were surely the worst.
Find the error: Of all the disasters that occured during the movie's production, the death of the two stars who performed their stunts were surely the worst.
Explanation
The subject of the sentence is "the death of the two stars", which is singular.
Therefore, the verb should also be singular.
The correct verb form is "was", not "were".