When DJ Kelly and her three fellow Seattle art gallery owners open their doors one morning, they don't expect to find a dead body on the floor. Who could this young woman be? And why has someone stabbed her to death and then ransacked their gallery? DJ's talkative inner voice doesn't have a clue, nor do her BFFs—Nita Marie, Jo, and Bobbie. None of their artwork seems to be missing. Maybe a framed photograph of a famous terrorist attack that apparently slipped under the copy machine during the burglary might hold a clue. Is this photograph a clue to the murder in their gallery? DJ isn't certain, but when a jaded, know-it-all detective belittles her capabilities and those of her pals, DJ convinces her friends that they should take matters into their own hands—and four new crime fighters are born.

Seattle senior citizen, DJ Kelly, and her three best friends and co-owners of the Waterfront Art Gallery, are detecting again. Despite an insistent internal voice that chides her for her risky adventures, DJ is not on the trail—this time to help Darlene, a nurse, who is trying to find a young man who was brought into the emergency room yelling a lot of strange, seemingly meaningless terms, including “CCR5,” and then who disappeared—possibly to the Psych Ward. Darlene has received a cryptic phone call from the young man and doesn't know where to turn. The four women fling themselves into the search, assisted by their old nemesis, Police Inspector Keohan, and the gallery’s handyman and king of malapropisms—Jerry. But their investigation suddenly takes a dangerous turn and the four ladies find themselves in serious jeopardy. Will they find the young man and unravel the mystery of his apparent mental breakdown before it’s too late? Is he insane? Drugged? Or just pretending? It’s all in the genes—and in this case, they’re “killer genes.”

When DJ Kelly and her fellow senior citizen partners at the Waterfront Art Gallery in downtown Seattle decide to take a vacation in Cannon Beach, Oregon, they have no clue that they will be immediately confronted with a skeletal hand buried on the beach, along with a mysterious box of rocks. As it turns out, the hand belongs to an infamous diamond thief who had robbed the Antwerp Diamond Center some years back and had escaped without detection. His two cohorts, who had been caught, but are now out of prison, are on the hunt for the missing diamonds. But they aren’t the only ones. Now, along with DJ and her three lady friends, add a couple of former Belgian policemen, the dead man’s sister, an errant lawyer, and the Gallery’s own malapropic handyman Jerry. The women also run into a police detective in Cannon Beach, who finds them as bothersome as their nemesis from Seattle, Detective Keohan, and things go downhill from there. But what has happened to the diamonds? What does the box of rocks have to do with the murder of the thief or the location of the diamonds? Does anyone know where the dead man has hidden them? The answer must lie in the mysterious box of KILLER ROCKS or does it? DJ is determined to find out.