When a debt collector is murdered, Holmes and Watson try to narrow down the suspect pool from thousands of consumers who owed the victim money. Meanwhile, Watson’s relationship with Andrew progresses when he asks her to meet his father for the first time.

Holmes and Watson investigate multiple motives for murder when a zoologist is killed because of his numerous love affairs or his trailblazing research. Also, Holmes finds himself the victim of identity theft after his medical records are stolen.

Holmes and Watson race to locate a missing woman when Harlan Emple, Holmes’ friend and “Irregulars” mathematics expert, becomes the prime suspect in her disappearance.