Click Beetle
I was picking up apples in the side yard[1], and found this grub burrowing into one.
These are commonly referred to as “wireworms”. Unlike most other insect grubs, they have a hard exoskeleton that makes them remarkably durable. They are hard to crush, hard to pull apart, and all in all have about the consistency of a piece of wire. They do have legs, which you can see above, but they barely use them and for the most part their behavior is quite wormlike.