Taking place four years after the events of the original film, John Hammond (Richard Attenborough) sends a team, led by Malcolm, to Isla Sorna, the second island InGen used to make the dinosaurs, to study the animals while coming into conflict with a team led by InGen to bring some of the dinosaurs back onto homeland.

References:
https://en.wikipedia.org/wiki/The_Lost_World:_Jurassic_Park