I caught this on Amazon Prime under the title TUNNELS. It's very low budget little effort that openly copies the superior C.H.U.D., but that doesn't mean that it's not a worthwhile viewing. I see that most people hate it on here, but I liked it regardless; the film is cheap and cheerful, designed to entertain with funny one-liners in the script and nice performances from the supporting cast members. Catherine Bach and Charlene Dallas make for a good pair of heroines in the CAGNEY & LACEY mould, while the likes of John Saxon and in particular the unknown Ray Tillotson give some very satisfying supporting turns. Okay, so the eventual reveal of the film's villain is a bit disappointing, but the '80s atmosphere is spot on.
Review of Criminal Act
