Piranha 3D takes place in the year 2010, in the underwater town of The Reef, located off the coast of Australia. A group of friends, including Christen (Emily Browning), Tom (Richard Kiley), and Lena (Margot Harder), are on a boat trip when a massive earthquake strikes, causing a landslide that unleashes a swarm of genetically modified super-piranhas into the waters. The piranhas, which have been lying dormant for millions of years, begin to wreak havoc on the town, devouring anyone in their path.