PI Carlotta Carlyle goes undercover in this outing, and that’s not exactly an easy task for a 6-foot tall redhead! Hired by a former colleague, she’s trying to determine the validity of fraud accusations lodged against a construction firm working Boston’s infamous Big Dig. Never a 9 to 5-ver, Carlotta’s also moonlighting on a missing person case. Rats, dogs, and lots of water play a major role in her investigations, which strangely enough, begin to merge. Carlotta relies nearly as much upon her instincts that her evidence, as none of the principals seems willing to level with her. When new love interest enters the scene, even he is not what he appears to be. More mystery than a thriller, The Big Dig is a light unprepossessing novel that in me, at least, evoked a bit of the spirit of Sam Spade.