错的,出现了两个谓语,regarded一个,is系动词一个
你这个句子意思有些混乱,应该是后面在前,我情不自禁喜欢上他,因为我认为他是个美男子在后
The reason why I couldn't help loving the man whose name is Johhny Depp （其实这个从句也可以改成 with the name of Johhny Depp) when I first saw his film called Pirates of the Caribbean （少一个从句,用过去分词吧,否则你用的从句太多了）was that I regarded him as a handsome man.
-> The reason why I couldn't help loving Johnny Depp when I first saw his film called Pirates of the Caribbean was that I regarded him as a handsome man.
这样也够复杂了,