Eddy; it's probably more than one mouse. It sounds like you don't want to kill it, which is fine.
These work great:
Humane-Mousetrap
It catches the mouse and then you take it wherever you want and release it--in fact, a cracker becomes a door in the release so he'll even have to eat his way out so you don't have to worry about him leaving hungry. Reload and repeat. It makes a pretty loud click when the mouse gets trapped, so you don't have to guess.
Have enemies? Give them mice.