I need help with Itunes?

Somthing went wrong with my itunes download. For some reason i was downloadin “the Alamo” and it was taking a long time so i left it on over night. When i woke up my comp. had went stand by or watever and when i turned it on and it said it was done but when i synced it . it would not play on my iphone. It says “Movie cannot be played.” There is aparently no way to redownload and i dont know wat else to try . Any help?