Does this image show the 'hook like thing'?

It could be a hornworm. The picture - though small - looks like the pupa (stage between caterpillar and moth). That it is below the soil, and about 3" down, also sounds like them. The "hook"-like thing might also be a clue. Though I've never seen this stage personally, I've seen lots of pictures, and the hook loops around at one end.

If it is a hornworm, then it would be an intermediate stage of one of the various sphinx moths. You might do a Google image search, and search on "hornworm pupa". That might determine if we are talking about the same thing.

If it doesn't have a real hook (more like a little handle), it would still be the pupal stage of a moth of some sort. LOL, I keep wanting to turn that little thing around on its other side, so as to see the handle. Or should I say, proboscis?

Too small to be the pupal case of a hornworm.

To determine who it is, put in a clear container with a lid; set it somewhere you'll see it each day -- but not in the sun.

A moth will eventually emerge at which time you can take a picture and post that for us. It's *much* easier to ID the adult than the pupa!