Dreamworks has released the first full trailer for director D.J. Caruso's I Am Number Four, starring Timothy Olyphant, Teresa Palmer, Kevin Durand and Alex Pettyfer. While the film's teaser trailer didn't really show much, this new trailer does a much better job at explaining what the story is about, in addition to showing some crazy new visuals from the sci-fi thriller.

Check out the new trailer below, followed by a full synopsis after the jump, and see all of our I Am Number Four trailers in the gallery! Watch for I Am Number Four in theaters on February 18th, 2011.

Three are dead. Who is Number Four? D.J. Caruso (“Eagle Eye,” “Disturbia”) helms an action-packed thriller about an extraordinary teen, John Smith (Alex Pettyfer), who is a fugitive on the run from ruthless enemies sent to destroy him. Changing his identity, moving from town to town with his guardian Henri (Timothy Olyphant), John is always the new kid with no ties to his past. In the small Ohio town he now calls home, John encounters unexpected, life-changing events—his first love (Dianna Agron), powerful new abilities and a connection to the others who share his incredible destiny.