The illegitimate daughter of a wealthy man becomes the target of her half-sister's plot to kill her to avoid sharing her father's inheritance. Not knowing why she has been targeted, the girl goes into hiding. Meanwhile, Inspector Rivera and Rex set out to find the missing girl.

When Rivera and Rex are called to investigate a double murder case, they find a baby girl inside a van. This leads them to uncover an illegal adoption racket, secretly run by a non-profit adoption agency. While trying to solve the case, Rivera and his colleagues at the police station are literally left holding the baby.