After years of pursuing Cullen Crisp, an infamous drug dealer, LAPD detective John Kimble arrests him for murder; a witness saw him murder an informant after getting information regarding the whereabouts of his ex-wife, Rachel, who allegedly stole millions of dollars from him before fleeing with his son. Partnered with former teacher-turned-detective Phoebe, Kimble goes undercover in Astoria, Oregon to find Rachel and offer her immunity in exchange for testifying against Crisp in court. Phoebe must act as a substitute teacher in Cullen Jr's kindergarten class at Astoria Elementary School. Phoebe gets a terrible case of stomach flu, falling ill at the last moment, so Kimble takes her place.