Laura and Rosemary are asked to restore an ornate water garden cascade in the grounds of a health spa, where they are invited to join owner Frances Caldecott and her children for dinner. That evening, the duo discover Frances has been strangled and her jewellery stolen, and set out to catch the culprit.

Laura and Rosemary investigate the mysterious death of a blind professor caught up in a bitter battle to save his beloved allotment from an unscrupulous land developer. A heady blend of weedkiller, cannabis and high finance hangs in the air as the duo search for clues - and another body is turned up before they track down the villain.