Titan A.E.

In 3028 A.D., humanity has mastered deep space travel and interacted with several alien species. A human invention called "Project Titan" alarms the Drej, a pure energy-based alien species. As the Drej start to attack Earth, Professor Sam Tucker, the lead researcher for "Project Titan", sends his son Cale on one of the evacuation ships with his alien friend Tek while Tucker and other members of his team fly the Titan spacecraft into hyperspace. When the Drej mothership destroys Earth and the Moon with a massive directed-energy weapon, the surviving humans become nomads, generally ridiculed by other alien species.
Fifteen years later, Cale is working in a salvage yard in an asteroid belt called Tau 14. He is tracked down by Joseph Korso, captain of the spaceship Valkyrie. Korso reveals that Professor Tucker encoded a map to the Titan in the ring he gave Cale. Tek tells Cale that humanity depends on finding the Titan. When the Drej attack the salvage yard, Cale is forced to escape aboard the Valkyrie with Korso and his crew: Akima, a human female pilot; and Preed, Gune, and Stith, aliens of various species.
On the planet Sesharrim, the bat-like Gaoul interpret the map and discover the Titan is hidden in the Andali Nebula. Drej fighters arrive and capture Cale and Akima. The Drej eventually discard Akima and extract the Titan's map from Cale. Korso's crew rescues Akima while Cale eventually escapes in a Drej ship and rejoins the group. Cale's map has changed and now shows the Titan's final location.
While resupplying at a human space station called New Bangkok, Cale and Akima discover that Korso and Preed are planning to betray the Titan to the Drej. Cale and Akima manage to escape the Valkyrie but are then stranded on New Bangkok when Korso and the rest of the crew set off for the Titan. With the help of New Bangkok's colonists, Cale and Akima salvage a small spaceship named Phoenix and race to find the Titan before Korso.
Cale and Akima navigate through the huge ice field in the Andali Nebula and dock with the Titan before the Valkyrie arrives. They discover DNA samples of Earth animals and a pre-recorded holographic message left by Cale's father. Professor Tucker explains that the Titan was designed to create an Earth-like planet; however, its power cells lack the energy necessary for the process. The message is interrupted by the arrival of Korso and Preed. Preed attempts to double-cross Korso, but he kills him. Moments later, the Drej attack the Titan. While the remaining crew of the Valkyrie distracts them, Cale - given the fact that Drej are, essentially, beings of pure energy - modifies the Titan to absorb them, thus re-energizing the ship. A repentant Korso sacrifices his life to help Cale complete the repairs. The Titan absorbs the Drej mothership along with everyone aboard and uses gained power to mold the ice field into a new habitable planet.
While on the newly-formed Planet "Bob" (named by Cale), Cale and Akima witness the weather of the new planet as it begins to rain. Stith and Gune leave on the Valkyrie as human colony ships approach the planet to start life anew.

Question: Who discover that Korso and Preed are planning to betray the Titan to the Drej?
Answer: Cale and Akima; Cale and Akima