The family of twin sisters Maddie and Abby Parker are placed in the FBI's Witness Protection Program after they witness a robber at the local museum, in which the priceless Kneel Diamond is stolen. Unfortunately, Maddie and Abby have a problem of being blabbermouths; as a result, everywhere the Parkers are sent to live, the girls inadvertently end up revealing their witness status. The gang is led by a crime lord with the rather unfortunate surname of Hatchew ("Bless you!"), who will do anything to get his hands on the diamond, which the thieves slipped into Abby's shoulder-bag during their escape from the crime scene; the gem ultimately ends up being set into her necklace. The family travels everywhere in the United States, from Texas to a prairie town, and eventually has been moved to every geographic location around the world possible, with the single exception of Australia – thus the FBI (who by this time are getting absolutely fed up of having to ''constantly'' relocate the Parkers, and all because Maddie and Abby can't keep their mouths shut!) send them to live in Sydney. The girls at first have much trouble, especially fitting in with peer group. Two assassins named Mac and Sidney are sent after them after having discovered their location by breaking into the FBI office. Maddie and Abby defeat Mac and Sidney by knocking them out, tying them to surf boards and putting clips in Sidney's hair, painting Mac's toenails and threatening to put bras on them. The twins manage to convince them to change sides; they leave after the girls lure Hatchew to Australia. He comes after them, manages to get the diamond and sets his thug on them. It looks like it's over for them until Mac and Sidney return and defeat the thug, saving the girls. Hatchew nearly gets away on a seaplane, but Maddie and Abby stop him using a boomerang and he is arrested by Katie, an undercover FBI agent posing as a lifeguard. The Parkers are finally able to return home to the United States wit