Ep 7. 42

The Doctor and Martha find themselves on board a spaceship that is hurtling towards a giant sun with only 42 minutes until impact. They soon learn that the ship's crew has been taken over by a sentient form of energy that is slowly killing them off one by one. The possessed crew members are relentlessly pursuing the Doctor and his companion, forcing them to race against time to stop the takeover and save the ship.

With communications down, the Doctor and Martha must work together with the remaining unpossessed crew members to try and find a way to squelch the alien takeover before all of the survivors are lost. The Doctor quickly deduces that the energy possesses its victims with a virus, and he advises the crew to isolate those who are infected in the hope of finding a cure.

As the situation grows increasingly dire and the possessed crew members become more volatile, the Doctor and Martha race to solve the mystery of the energy's origins and find a way to halt its spread before it's too late. In the process, the Doctor is forced to confront his own mortality as he faces the very real possibility of sacrificing his own life to save the ship and its crew.

As the clock ticks down and the ship's systems begin to fail, the Doctor and his companions find themselves in a race against time to save not only themselves but also the entire ship and crew. Will the Doctor and Martha be able to outsmart the malevolent energy and find a cure for the possessed victims, or will they become unwitting sacrifices to the giant sun just a few minutes away? The action-packed episode is full of high-stakes drama, tense moments, and plenty of cliffhangers that will leave viewers on the edge of their seats until the very end.