Twins Justine and Perry have left their home in Australia and embarked on the road trip of a lifetime in the Pacific Northwest.

It's been a year since their dad lost his battle with cancer and Justine became the sole caregiver for her autistic brother, Perry. Now Perry has been accepted into an assisted-living residence in their hometown, Brisbane, Australia, but before he takes up residence, they're seeking to create the perfect memory.

For Perry, the trip is a glorious celebration of some of his favorite things: Ogopogo, Jackie Chan movies and earthquakes. For Justine, it's an opportunity to learn how to let go—of Perry, of her boyfriend, Marc—and to offer their mother the chance to atone for past wrongs.

But the instability that has shaped their lives will not subside, and the seismic event that Perry forewarned threatens to reduce their worlds to rubble...