No need to worry! In your situation, you could easily recover your deleted movies completely with the help of a free hard drive recovery tool that has helped my friend recover his inaccessible photos and files from a WD flash drive.
All right, one more thing, have you rewritten your original data? In fact, anything new saving on this hard drive can erase your original movie data. Therefore, you should keep it free from any new data till you retrieve your data back.
Note: You should back up your important data frequently in the future.