Foregone Conclusion by Larry Darter

When two private investigators team up to recover some ridiculously expensive stolen jewels, together, they must push their skills - and their lives - to the ultimate limit. And along the way, they discover the true meaning of loyalty and friendship...

When a single diamond surfaces fifteen years after an armed robbery crew pulled a daring daylight heist, the biggest jewel theft in LA history, the insurance company that absorbed the costly claim, hires Malone to look for the rest of the missing $68 million worth of the rarest and most valuable gemstones on the planet.
Finding the diamonds means Malone must first find Kyle Murray, the sole surviving member of the crew who recently completed his fifteen-year prison stretch for his part in the robbery. But Malone finds it isn't easy to find a man determined not to be found. Murray's trail takes Malone through California, then to Toronto, Canada, and finally to New Zealand.

While looking for Murray, Malone suddenly finds himself drawn into a deadly game of cat and mouse - and he's already several moves behind - with two other people determined to find Murray and the diamonds before he does. And their first attempt to kill Malone to rid themselves of the competition is only the beginning...

Malone and his former protégé, Honolulu P.I. and New Zealand ex-pat T. J. O'Sullivan, team up once again. And they must find Kyle Murray and the diamonds fast - while heading for a showdown that may well be their last.

Foregone Conclusion is the fourth novel in the thrilling Malone Private Investigator Series of Crime and Suspense Thrillers. If you like breathtaking action, and laugh-out-loud humor, with a hint of romance, then you'll love this edge-of-your-seat detective story. Perfect for fans of Robert B. Parker's Spencer, Raymond Chandler's Philip Marlowe, and Ace Atkins' Quinn Colson. You may enjoy reading the Malone series in any order.