Trama

A Las Vegas cabbie enlists the help of a U.F.O. expert to protect two siblings with paranormal powers from the clutches of an organization that wants to use the kids for their nefarious plans.

In Las Vegas, regenerated ex-con Jack Bruno works as a taxi driver. During a UFO Convention at Planet Hollywood, the skeptical Jack picks up Dr. Alex Friedman, who will present a scientific lecture at the event. Then he is pressed by two henchmen of his former boss, the criminal Wolff, who wants to talk to him, but Jack does not want to return to the crime life. Jack fights and gets rid of them; out of the blue, he finds two teenagers on the backseat of his cab. They say they are siblings, Sara and Seth, and they need to travel to a location outside Las Vegas in the middle of nowhere. Meanwhile, the government finds a spacecraft that crashed near Las Vegas and chases the two aliens; after the investigation of the men of Major Henry Burke, they discover that the two siblings are the aliens. Jack Bruno, Sara and Seth are chased by Henry Burke's team and by "Syphon", a killer from outer space sent to kill them by their planet's military that wants to invade Earth. Sara and Seth explain that they traveled to Earth to collect scientific data of an experiment and save Earth from invasion, but they need to return immediately to their planet. Jack teams up with Dr. Alex to retrieve their spacecraft in a secret base in Witch Mountain.—Claudio Carvalho, Rio de Janeiro, Brazil

After crash-landing their fast spaceship on the Earth, somewhere in the hot deserts of Searchlight, Nevada, the teen, human-like extraterrestrial siblings, Sara and Seth, end up in the back seat of the former mob getaway driver and now a Las Vegas cabbie, Jack Bruno. Now, with their lives, and the fate of their world, lying in Jack's hands, the twins embark on a frenzied adventure in the wilderness, as the U.S. Homeland Security agents and an armed-to-the-teeth alien bounty hunter are hot on their trail. Now, the race is on, and the unlikely team's only chance to succeed in their dangerous mission lies deep in the heart of the mystical Witch Mountain. Can they make it in time?—Nick Riganas

A middle-aged male taxi driver and a middle-aged female scientist must work together to help two teenage alien siblings who are trying to get back home. However, a sinister government agency is hunting down the alien siblings so they can test experiments on them.—RECB3

News of UFO sightings around Earth are increasing steadily. An alien spacecraft crashes near Searchlight, Nevada, 45 miles outside of Las Vegas. Project Moon Dust, a secret Defense Department unit led by Henry Burke, reach the scene of the crash in black helicopters. Men in black seize the spaceship and search for its passengers to harness their DNA and powers. The team headed by Henry reaches the impact side and tracks 2 aliens in humanoid form escaping from the crash. Henry starts to analyze the site and finds 2 sets of footprints. Henry sends out an alert to all law enforcement to look for anomalies in a 50 mile radius.

Jack Bruno (Dwayne Johnson) is a former mob getaway driver and now a cab driver in Vegas. Bruno is dropping off passengers to the UFO convention at Planet Hollywood. One of his passengers is Dr. Alex Friedman (Carla Gugino), a failed scientist who is giving speeches about legitimate scientific theories of UFOs and outer space at the Planet Hollywood hotel. Back home, Bruno is faced with multiple unpaid bills. He watches on the news as the media terms the UFO impact as a chlorine spill, which required a 5-mile security perimeter to be established.

Bruno fends off two thugs who seek his services for mob boss Andrew Wolfe. After fighting them, Bruno drives off, later noticing two children, Sara (AnnaSophia Robb) and Seth (Alexander Ludwig) sitting in the back seat of the cab. They tell him they need to go to a certain destination and are willing to pay all they have ($15,000) to get there. On the way they are intercepted by Major Henry Burke (Ciarán Hinds) who tracked them through various discoveries such as their footprints being tracked to a bus stop, stolen clothes, a car being burglarized, a bus heading to Las Vegas, and an ATM being deprived of all of its contents (which were $15,000 exactly without using a card), which eventually pinpoints their location in Bruno's taxi.

Henry intercepts Bruno's cab in the middle of the desert, which he was on his way to drop the kids to their destination. Henry wants to apprehend the aliens, but Jack thinks these are Wolfe's men & crashes them away in a car chase. Seth's ability to vary his molecular density, as well as Sara's Telepathy and Telekinesis, helps the group to escape. Seth simply stands in front of Henry's vehicle, and it crumbles as it crashes into him. Bruno doesn't know they are aliens. They lead him to a run-down house in the middle of nowhere.

When they arrive at the house, the children tell Bruno that they will be re-united with their relatives soon. Bruno decides to follow them, which leads him to the basement of the house. Though grateful for his concern, the children tell him they must continue their journey without him, as they can trust no one. There the kids retrieve an object from a plant inside a huge underground bio-lab before they are attacked by a creature who destroys the lab. Jack escapes with Seth and Sara.

When leaving they are attacked by a "Siphon", a creature built to destroy a certain target, in this case the children. The Siphon pursues them until it causes a crash of his spaceship into a train, the creature survives, though wounded.

The kids explain to Bruno that they are aliens from a dying planet located 3,000 light years from Earth and can travel by using wormholes on their spaceships. Its government intends to invade Earth, despite the majority of their race being fully opposed to the plan, so that their kind may survive. Seth and Sara's parents are scientists who sought a way to save their planet without invasion but were arrested before completing their experiment. The teenagers came to retrieve the successful results. They also explain that the object they obtained at the house contains the results of an experiment which their parents set up. The research from this experiment will save their planet without having to attack and invade Earth. But the alien government (who still plans on invading Earth rather than trying to save their home planet) sent the Siphon to stop them. To prevent the invasion from happening and save both worlds, they must retrieve their spaceship and return home with the results.

They find Dr. Friedman at the UFO Expo, who is familiar with outer space and travel. Despite initially dismissing Bruno's story, she believes him after Seth and Sara show off their powers and narrate their current situation. Realizing that the teenagers are what she has been searching for, Friedman joins the group.

They meet fellow UFOlogist and conspiracy theorist Dr. Donald Harlan, who reveals that the spaceship was taken to Witch Mountain, a secret US government base. Harlan and his men distract the soldiers with Bruno's taxi while the others escape to Witch Mountain in Harlan's RV after evading the Siphon. Sara uses her powers to knock the Siphon through a wall. Henry arrives at the convention to capture the aliens.

Jack, Alex & the kids escape using help from Alex's convention friends. They reach Witch Mountain but are captured by Henry's forces. Henry orders that the teenagers be prepared for vivisection, but frees the adults, confident that nobody will believe them. Jack pretends to give up & Henry lets him go, but that is just a ruse to free himself.

The Siphon causes a distraction by attacking the base. In the confusion Jack & Alex manage to free the children and reach their ship. By running the Siphon over they can escape but the Siphon hangs on and gets on board. Bruno and Seth battle the Siphon in the lower sections of the ship, unmasking him in the fight. Finally, Bruno defeats the evil alien by knocking him out of the ship's airlock, which kills him.

Nothing is mentioned about the fate of Henry Burke, though he was last seen disappointed and upset for his failure and was talking to his boss on the phone, with a possibility of getting fired. The kids drop Jack and Alex off and after a tearful goodbye, they head back to their ship but give Bruno and Alex a device that will allow the kids to always find them. And Sara gives Jack the power to use his brain for mind reading ability.

Bruno and Dr. Friedman (now a couple) speak at a UFO convention about their new successful book called "Race to Witch Mountain". They promote their book and knowledge on the UFO convention circuit, explaining that the publicity protects them from government reprisal. As they leave the convention, the alien device activates, implying that the alien teenagers may be returning to Earth.