1×10 January 24, 1997
SHELL GAME (Serial 7, Episode 2)
Setting: Kennedy Space Center, Florida, and Mondas, 2003
Regular Cast: Hugh Laurie (The Doctor), Sarah Michelle Gellar (Lizzie Thompson)
Guest Starring: Ed Begley, Jr. (Director Slate), Don S. Davis (General Cutler), Leland Orser (Mulchay), Peter Cullen (voice of the Cyb Leader)
Plot: On Mondas, the Doctor and Slate are taken to Cyb Command, located inside a mountain sculpted into the shape of a Cyb helmet. To prevent their escape, the imprisoned scientists are forced into magnetic boots. The Cybs prepare to convert the humans, but the Doctor’s alien biology causes their machinery to malfunction. On Earth, Lizzie observes the Cybs using their technology to shield certain NASA systems from the effect that has blocked the humans’ weapons. She guesses that the Cyb space ships are only capable of one-way flight, and they need NASA’s technology to return to their own planet. Mulchay, a junior scientist, suggests that the space center’s RF isolation room might offer similar protection. General Cutler, Lizzie and Mulchay break away from the group and are chased by a Cyb to the isolation room. Once inside, Cutler’s gun does function again, but it proves ineffective against the Cyb. However, when the Cyb enters the room to dispatch the general, it suddenly collapses and expires. Lizzie opens the Cyb’s suit and discovers that it is mostly hollow inside. The organic components heavily atrophied, and the cybernetics have been streamlined and optimized. Mulchay notices that the Cyb body contains no power source, and must be powered by an outside broadcast source. Armed with the Cyb’s weapon, Cutler manages to liberate Mission Control. NASA reactivates Mission Control using Cyb technology, hoping to launch Constitution to recover the hostages on Mondas. Inside the spaceplane, they discover the Cyb machine responsible for the power drain. Mulchay and Lizzie determine, to the general’s dismay, that attempting to disable the machine will cause a massive explosion. A surviving Cyb attacks them, and Lizzie directs the output of the energy transfer device to destroy it by a massive overload. Lizzie believes that the Cybs always intended to destroy the Earth, and realizes that the Doctor’s reference to gravity was a clue: if Mondas was truly a twin to Earth, its proximity should be causing massive tidal forces. On Mondas, the Cybs repair their conversion machines. Just in time, the Doctor helps the scientists escape by using his sonic screwdriver to release their magnetic boots, allowing them to leap away in the low gravity. During their long journey in deep space, the Cybs consumed most of their planet’s matter as reaction mass to control their travel. Too much energy from Earth will saturate their planet and destroy it, and the Cybs must destroy Earth before this happens. Slate sacrifices himself, staying behind to help the others escape. On Earth, General Cutler orders Constitution launched on a collision course toward Mondas, so that the energy transfer device will explode and destroy the planet. Due to Mondas’s smaller mass, the force from the explosion would devastate the facing side of Earth, so Mulchay works with Lizzie to disable Constitution. The Doctor and the NASA scientists make their way back to Constellation, and are confronted by Director Slate, now a Cyb. By appealing to his sense of duty, the Doctor manages to break through to his original personality long enough for them to launch the spaceplane. The Cybs on Mondas send a remote signal to detonate the energy device, but Lizzie is able to block it just in time. More Cybs arrive on Earth via Verne Gun and retake Mission Control. Cutler, Lizzie and Mulchay defend the space plane, but Mulchay is mortally injured. Constellation lands, and the Doctor attempts to negotiate a peaceful solution. Mondas is close to saturation, and the Doctor offers the Cybs peaceful resettlement in Earth’s uninhabitable regions. The Cyb leader defends their actions in the name of preserving their race, and claims that the Cybs can not survive without a re-energized Mondas; there is no way to preserve both planets. Before the Cybs can take control of the energy device, the dying Mulchay turns its output all the way up, transferring a massive amount of energy to Mondas. The planet saturates with energy and disintegrates, causing the Cybs on Earth to die with their power source. The sight of Mondas breaking up triggers memories of his own planet’s destruction, and Lizzie has to drag the shell-shocked Doctor back to the TARDIS.