Something with a pretty UI that's easy to use, I have no idea, but you should try to find one of those if you don't know what you're doing. After you've done that and it's failed (or if you do know what you're doing) try the low level advanced tools at
CGSecurity - Data recovery: TestDisk & PhotoRec
Hope you've just lost a partition table and testdisk can save it.
If you haven't lost a partition table, and testdisk can't save it, photorec will recover anything that is still readable on the drive.
Testdisk is the dangerous one - it writes partition tables and actually makes changes to the disk. If it works, it recovers everything easily, but if it doesn't, you can make things worse - that's why I said to use something else with a pretty UI that you can't screw up first.
Photorec is safe, it doesn't write to the disk so it can't screw anything up, but it's the tool of last resort - it loses filenames and directory structures, and recovers everything that can still be read. Everything. You'll probably get most of your films back, but you might end up with gigabytes of temporary internet files from a browsing session ten years ago to sort through too.