In Beverly Hills, California, wealthy businesswoman Vivian "Viv" Ashe leaves her richly pampered pet chihuahua, Chloe, with her irresponsible niece, Rachel, while she embarks on a business trip for ten days. Papi, the gardener Sam's pet Chihuahua, has an unrequited crush on Chloe, by which she is disgusted. On a whim, Rachel decides to go to Mexico with her friends and brings Chloe along. When Rachel leaves Chloe alone in the hotel room to go dancing at a club, Chloe goes looking for her, but gets dognapped as she tries to find Rachel and is sent to the dog fights in Mexico City. There, she meets a street-smart German Shepherd named Delgado. Rachel comes back to the hotel and is frantic when she finds Chloe missing.