Snow Bright and the tooth magician Book

Another late career Westlake caper.

A thief breaks into a scientific laboratory owned by the evil tobacco companies. He gets caught, and injected with some formula, then takes some more, thinking it's an antidote. This turns him invisible somehow.

He quickly begins stealing more valuable stuff. The tobacco company wants to get its hands on him, and so do a whole lot of other unscrupulous people.

Not bad, but like a lot of Westlake's work at this time, seems out of date, even for the time.