External drive no long mounting after Time Machine hang

Hello all,

I had a backup of one laptop on an external drive, and then plugged the same drive into my wife's computer and ran Time Machine to back it up. It was taking forever (as in 1K transer after about 5 min), and I restarted the machine and tried again. Time Machine wouldn't recognize the backup it started, so I deleted it and started again.

Same thing, it hung.

I unplugged and figured I'd tackle it another time. I went to plug back into the original system and now the drive won't mount properly. It takes a long time to come up, and then throws a warning that the disk wasnt ejected properly, and only 2 of the 3 volumes show in the Finder. Disk Utility shows the 3rd volume greyed out and won't do anything with it.

I can't copy files from the 2 volumes that do appear, and of course I have files on this "safe" backup drive I need now. Disk Utility will show them, but can't verify/repair.

Anyone know if it's possible to rescue the files? I've looked a bit and seen some mixed reviews on apps for rescuing files. This seems unlikely if Disk Utility won't access the files.

Thanks for any helpful information,

Markie