In Barbie: Dog-Gone Mystery!, when their summer jobs are unexpectedly cancelled, Barbie "Malibu" Roberts and Barbie "Brooklyn" Roberts start a business of their own: pet sitting for their neighbors! On their first day, Barbie "Malibu" and Barbie "Brooklyn" are excited to take Trixie the dog out for a walk. But when they arrive, she's nowhere to be found! Can these BFFs solve the mystery and bring Trixie home?