Great movie (7)
I believe the answer is:
titanic
I believe this clue is a double definition.
'great' is the first definition.
(thesaurus)
'movie' is the second definition.
(I've seen this before)
(Other definitions for titanic that I've seen before include "Doomed liner found in attic" , "Gigantic like doomed ocean liner" , "Ill-fated vessel" , "Ship sunk by iceberg" , "made of metal" .)