When an insatiable great white shark terrorizes the townspeople of Amity Island, the police chief, an oceanographer and a grizzled shark hunter seek to destroy the blood-thirsty beast.

Years after Tess and Anna endured an identity crisis, Anna now has a daughter of her own and a soon-to-be stepdaughter. As they navigate the myriad challenges that come when two families merge, Tess and Anna discover lightning might indeed strike twice.