The film starts out following a truck that is transporting something for the government. The truck is escorted by military personnel and government agents. While making its drive, the truck is attacked by an onslaught of black sedans. The first indicator that the story is based in the Pokemon universe is when the men in the sedans start unleashing their pokemon, which then attack the truck and its escorts. The soldiers and the agents unleash their pokemon as well, but they are overwhelmed. Once all is over, one of the men from the sedans breaks into the truck and steals its cargo: a single, black pokeball.
The film then turns its attention to Ash Ketchum, a teen from Pallet Town. Ash is a dreamer that has always wanted to become a pokemon trainer, but his mother has forced him to stay at home until he finishes school. In the mean time, Ash quenches this desire by volunteering at the local science lab run by Professor Samuel Oak. Ash’s biggest annoyance in his time spent at the lab is Oak’s grandson, Gary, who constantly makes him look bad by doing a better job.
One day, Ash gets his chance to fulfill his dream. Lieutenant Lucas Surge, a former military man and old friend of Oak’s that now works for a government agency, comes to Oak’s lab seeking help. Surge explains to those present (Oak and Gary) that a rare pokemon that was being transported to a hidden nature reserve has been stolen; Ash is eavesdropping throughout this whole explanation. Surge believes that the man responsible is a suspected crime lord named Giovanni Roquette. Surge explains also that Roquette is holding a pokemon tournament within the next few weeks. Surge wants Oak to compete (Oak being a former champion of the Pokemon League) as means of retrieving the stolen pokemon or getting enough evidence on Roquette to put him away. Oak refuses, but Gary volunteers to go in his place. At this moment, Ash comes out of his hiding spot and volunteers also.
Oak is reluctant to send either of the boys, but Surge takes them both willingly. Seeing no other choice, Oak bestows upon both Gary and Ash six pokemon. Gary takes an assortment of powerful pokemon, but Ash must take what is left over. Most notable among these is pikachu. Oak had avoided using the reclusive little rodent, as it would not stay in its pokeball nor be reasoned with. However, it is all that is left, so Ash must make do. Somehow Ash gets in touch with the electric mouse’s emotions and gains its trust. After all of this, it’s off to the tournament.
Before the tournament begins, Roquette becomes aware that Surge’s agency will have men competing. Thus, the crime lord assigns his two most disposable people to compete: Jesse and James. Jesse and James are the separated traits of a girl found in The Hills: one is beautiful and the other is stupid. Beside the point, Jesse and James are put into the tournament to weed out whoever it is that Surge has used to infiltrate the tournament.
So, the tournament begins with the following competing: Ash, Gary, Jesse, James, Misty, Brock, Erika, Koga, Blaine, Sabrina, Lorelei, Bruno, Agatha, and Lance, as well as a mystery champion that Roquette has chosen to compete against whoever wins the most battles. Ash makes friends with fellow competitors Misty and Brock, who specialize in water and rock type pokemon respectively. In the meantime, Gary makes friends with Lance and the others that make up the Elite Four of the Pokemon League. As the tournament goes on, Ash remains focused on the goal at hand as well as trying to win battles; Gary is focusing only on the latter. Snooping around with his new friends whenever possible, Ash tries to locate the stolen pokemon or any evidence to the fact.
Eventually, the tournament comes down to Ash versus Gary in the round just before the semifinals. Gary has been corrupted by Roquette’s organization and is given more powerful pokemon in exchange for eliminating Ash. Ash, to everyone’s surprise, actually manages to beat Gary and advances to the semifinals where he must face Lance. Gary goes home ashamed and guilty. In the battle with Lance, Ash is nearly defeated, but, with a wink, Lance actually throws the battle. Ash wins and advances to the final round to fight Roquette’s mysterious champion.
As it turns out, the champion is not a trainer, but a pokemon called Mewtwo. Roquette has used the DNA of the stolen pokemon, Mew, and created a new, supreme being. Ash loses the battle badly. Once Ash is defeated, Roquette moves to put Mewtwo back inside its pokeball, but the creature will not go. Instead, Mewtwo turns on the crowd and its master. All spectators flee the stadium. Roquette is destroyed by a blast of Mewtwo’s psychic energy and then it turns back on Ash.
With all of the tournament competitors rushing out onto the battlefield, as well as Surge, together they and Ash put up a fight. Throughout this mess, Mewtwo stills holds its own. Pikachu, in a last desperate attempt, appears to sacrifice itself as it jumps onto Mewtwo’s body and calls down a lighting bolt. When the smoke clears, both Mewtwo and pikachu appear to be dead. Ash rushes to his fallen companion’s side and, after a minute of tears, is glad to find pikachu is still alive. Mewtwo is dead and its body is hauled off by Surge’s men. Surge thanks Ash for his assistance and offers him a chance to accompany the team on the escorting of Mew to its reservation. Ash goes along and the film ends with Mew being released into the reservation and flying away.
It would be hard to do this film in the same manner as the story of the video game goes. An entire movie alone could be done of Ash just fighting Brock at his gym. The story had to be tweaked so everything could fit into one film. As someone who played that game as a kid (still do occasionally) and watched the television show, I’m very comfortable with the direction I’ve gone in here. Whether any one else agrees is none of my concern.
Cast
Ash Ketchum- Logan Lerman

Gary Oak- Aaron Johnson
Professor Samuel Oak- Michael Caine
Misty- Brittany Snow
Brock- Taylor Lautner
Lieutenant Lucas Surge- Stephen Lang
Erika- Jamie Chung
Koga- Ken Watanabe
Blaine- Kurtwood Smith
Sabrina- Selma Blair
Lorelei- Laura Prepon
Bruno- John Cena
Agatha- ??? (I’m going to need some help on this one folks.)
Lance- Rain
Giovanni Roquette- Julian McMahon
Jesse- Helena Bonham Carter
James- Russell Brand
Mewtwo (Motion Capture) - Doug Jones