I wouldn't recommend seeing this movie unless you want to see a crappy version of Twilight, which in my opinion, was also a crappy movie.
The movie is about John, Number Four, a teenager from another planet that's in hiding from a group of aliens that destroyed his planet and followed him to Earth. John was sent to Earth with his protector, Henri, who is responsible for training John to learn and use his special gifts while keeping him out of detection of the “Mogs”, the aliens that destroyed his planet. The movie opens with the death of Number 3, which triggers John’s “powers” to start developing. Henri explains to John his role in life and what everyone gave up for him to live. Henri continues to explain that the Mogs can only kill him and the others in order and since 3 died, he is next. After an involuntary display of John's “powers” get posted on YouTube, John and Henri are forced to move to the MidWest to disappear from detection of the Mogs. Assuming the Mogs would never expect them to move to Ohio, John and Henri burn everything they own and find a low key place to live. After settling into his new house in Ohio, John, bored with his life of hiding, enrolls into the local High School. Only to find that the popular kids don’t like him, John of course, befriends a nerd and meets an "outsider" girl and they fall madly in love. In one of the least surprising events, Sarah old boyfriend is...what a shock...the Quarterback of the football team and now wants Sarah back. The nerd "Sam" discovers that his dad, who had disappeared years ago, was actually helping Henri and fighting against the Mogs Aliens. All the while John and his Sarah are falling deeply in love while Henri tries to explain how John is only going to put everyone in harm's way. In the midst of John and the Quarterback fighting over Sarah, the Alien Mogs finally catch up with John and Henri. While trying to save John, Henri is killed but not before Number 6 jumps in to save John and show off some powers of her own. A few action screens happen and the introduction of Number 6 slightly brings your hopes up, but by this time the movie is almost over. In the end the Mogs take John’s girlfriend Sarah which forces John to team up with Number 6 and Sam to fight to save John's “One True Love”.
Overall the movie is boring and unoriginal; imagine Twilight with Aliens instead of Vampires. The movie was not enough super hero or SiFi to be a good action film and the story was too weak to be a thriller or a romance. I like Timothy Olyphant (Henri), he's great in Justified, but even he couldn't save this movie. The acting is good and the effects are well done but the writing and story are terrible. How they didn't get sued by Twilight, I'll never know. Catch it on TV if you must, but it's not worth rental.