When private investigator Rómulo Aitken has to hire a new octogenarian mole because his go-to guy has injured his hip, 83-year-old Sergio figuratively jumps at the chance. His mission: go undercover in a nursing home to find out if there's any truth to their client's suspicion that her mother is being mistreated. As Sergio struggles to balance the assignment with his increasing involvement in the lives of residents, this charming and stylish Chilean documentary shifts from spy comedy to a warm-hearted reflection on old age and loneliness.