This episode has a nod towards 42 which according to Douglas Adams is the answer to life, universe and everything. It s also roughly how long Doctor Who episodes last so its as near to getting a real time episode as you can get.
The Doctor has just wired up Martha Jones' phone so that Martha can phone anyone she likes wherever and whenever she is in time and space. The Tardis lands on a spaceship and when the two occupants step outside, they are overcome by the heat in the other spaceship. When the two go through an airlock, the door is closed and they are unable to get back due to the heat from the ship. The larger craft is heading towards a star and will burn up in 42 minutes.
The Doctor is introduced to the crew captained by Kath McDonnell played by guest star, Michelle Collins of EastEnders fame, a British soap opera.
Martha and crew member Riley attempt to make it to the bridge of the ship in order to turn the ship around. Between the start location and the bridge is a series of air locks which can only be answered by a code which is the answer to a question. One of the questions is what number is next in the series which The Doctor works out. Another question is who had the most number one hits, the Beatles or Elvis. For the second question, Martha calls her mum who checks the answer on the internet.
Korwin, another member of the crew is feeling unwell in the medical bay. The rest of the crew including The Doctor and Martha go to the medical bay. Korwin has been taken over by a parasite. The Doctor tranqualises Korwin using his sonic screwdriver which works but not for long, Korwin eventually recovers and begins killing people with light from his eyes. Korwin uses a heavy work helmet to prevent unnecessary use of his light weapon. The dead are burned alive and all whats left is burn marks on the wall or floor.
In order to escape Korwin, Riley and Martha hide out in an escape pod which Korwin jettisons into space. The Doctor has to don a spacesuit to go out side the ship to activate a recall of the escape pod. Once outside the ship, the Doctor discovers that the star that the ship is falling into is alive. When the Doctor is returned to the ship after successfully calling the escape pod back, the Doctor is taken to the medical bay in order to freeze his body to kill the parasite. The power to the freezing machine is cut and
Kath lures Korwin into an airlock where she then opens the airlock and both Korwin and herself are pulled out into space therefore saving the crew.
Riley and Martha get to the bridge and after jettisoning some fuel, they manage to turn the ship around and save the remaining crew. The Doctor and Martha depart. Martha calls her mum again and then once the call is over, Martha's mum speaks to some suited people who then leave.