You might call Bertha Cool the broad beam of the Cool and Lam Detective Agency. As this story begins, all 200-odd pounds of her are quivering happily at the thought of a fat fee to come.

All Bertha has to do is guard the priceless treasures of wealthy explorer Dean Crockett II, who is about to throw a fabulous party. But somebody''s hand is quicker even than Bertha''s gimlet eye, and one valuable jade Buddha and a primitive blowgun disappear.

That''s when brainy bantam-weight Donald Lam steps in, and the pace sets off fiercely, before reaching a sensational, unexpected climax.