The Empty Planet

Part 1

Sarah Jane tells Mr Smith to do a maximum scan. Clyde asks what is going on; Rani says Mr Smith picked up an alien energy trace for a second, which then vanished into the signals of every energy source on Earth. When they leave Sarah Jane's house, Rani reminds Clyde of their school assignment (to read Great Expectations), which Clyde sees no point in considering they might be invaded. Rani's dad comes to see her in her room, but she asks him to leave so she can finish reading the book. Clyde's mum also comes to see him.

The confusing mix of signals is suddenly cut out. Rani wakes up to find her parents missing, and there is no-one in sight outside. Sarah Jane is also gone, and Mr Smith no longer appears to be in the computer that houses him. Rani searches for another person, finding that nothing has a signal anymore. She prays that she is not alone, when she hears a knock at the door and opens it to find Clyde. They head into town to look for someone besides them.

They can't find anyone, but realise that if everyone suddenly disappeared there should be crashed vehicles everywhere. There are not, which means that whatever took the humans didn't want to do any damage. They go to a cafe for breakfast and try to figure out why they have not been taken. They decide to go back to the attic, and see crates being knocked over. They spot another person, who runs away, and chase him to an apartment block. He is a schoolboy called Gavin, who rather than being relieved is afraid of them. Rani and Clyde try to convince him they mean no harm, and Rani tells him about aliens to try to gain his trust. Gavin is sceptical, but before they can persuade him to help, a strange noise is heard and he slips away whilst Rani and Clyde try to work out what it was.

They go back to the cafe and see a strange image on all the screens, even the mobile phones. They hear a noise getting closer and go investigate. Rani notices Gavin and goes down an alley; Clyde looks around the corner and sees a yellow robot. He is cornered by it, whilst Rani is cornered by a red one. The robots reveal their guns and prepare to fire...

Part 2

Gavin pushes the robot in front of Rani against the wall so they can escape. Clyde runs away from the yellow robot and hides in a store. He gets away from it and meets up with Rani and Gavin. They look at the images on the screens and go in search of the robots, then decide to return to the cafe. Rani and Clyde talk about what makes them different, mentioning time fissures, space travel and the TARDIS, much to Gavins confusion. Clyde realises the Judoon grounded him and Rani on Earth, so the robots had to leave them behind to avoid breaking the law. This doesn't explain why Gavin is still there as he knows nothing about aliens.

The robots suddenly burst into the cafe. They escape out the back door and tell Gavin to get away, splitting up to distract the robots. They are cornered once again and the robots scan them, but do not kill them. In the cafe, Clyde shows them a newspaper so they can quickly learn the human language. They reveal the strange image is a countdown. They demand the air and the sun, saying that if it is not given to them by the end of the countdown the human race will not return. Rani realises that they don't mean 'sun and air' but 'son and heir'. It turns out that Gavin's father was an alien king, who has now died. The robots have come to take Gavin to their planet and sent the news he is a prince in the energy trace, but Gavin never received it.

Clyde and Rani search for Gavin, eventually locating him at The Ealing Circle Nature Reserve. They find that Gavin is wearing a bio-damper to shield his alien half; when this is removed, the robots send him the information again and show him the planet he is meant to rule. He agrees to go and orders the robots to return everyone to Earth. He names the other two Lord Clyde and Lady Rani as he leaves. Mr Smith fixes the records so that Gavin has officially moved to Australia. Clyde and Rani think about the fact that if they had never met Sarah Jane, they would have been in big trouble.

Continuity

Production

As in The Mark of the Berserker, Sarah Jane is only briefly seen. With Luke Smith and K-9 off at Oxford, Rani and Clyde are the principal characters, with one or both appearing in every scene.