At last, Shelby Belgarden has put her crime-solving behind her and has returned to the life of an ordinary teenager. Now 16, she has taken her first job: working at a new local restaurant called The Steak Place. But when one of her co-workers -- a waitress named Nadine -- goes missing, Shelby suspects foul play. The police won't believe her. Neither will Shelby's boyfriend, Greg, who grows frustrated with her search for a criminal who may not exist.

With school over, Greg visiting relatives, and Betts on vacation with her family, it's looking like it will be a quiet summer for Shelby Belgarden. Until, that is, she finds out that Betts and her family have returned home suddenly, and Betts's mom faces criminal charges in the theft of a computer program from her workplace.

To save Mrs. Thompson's job and reputation - and to keep her out of prison - Shelby infiltrates the company in order to dig up clues. But with no clues to be found, can Shelby find the answers that will keep Betts's family together?