The Graske stole other aliens and put them into pods.

The Graske are small aliens who come from the planet Griffoth. They stole aliens from other worlds and put them into pods to feeeze. Then they put duplicates of the aliens on there planets. The Graske stole aliens such as Slitheen, Scholars, Humans and even Zygons. The Doctor damaged the pods and the Slitheen chased the Graske away. The aliens were returned and the duplicates were destroyed.

Sarah Jane Smith then fought the Graske. It turns out that the Graske was working for the Trickster as his henchman. The Graske teleported to Earth after Sarah Jane was eraised from time. The Graske chased Maria Jackson and eraised her from time. The Graske then returned and chased her father Alan. But then Alan caught and tied up the Graske. The Graske gave Alan his teleporter and her managed to get Maria back and Sarah Jane partly back. The Graske managed to untie himself and he teleported away.

In a short adventure the Graske fought the Doctor again in his Tardis. He wanted Earth but the Doctor foiled his plans and the Graske lost. He teleported away.

Graske of Griffoth
The Graske fought Sarah Jane again and he was working with the Trickster. The Graske disguised himself as a boy from Sarah Jane's childhood. He made her want to go back to the day her parents died. He called himself Oscar. Sarah Jane did go back and she saved her parents. She also gave the Earth to the Trickster. In the present day the Graske chased Rani and Clyde. They were there when time had changed. The Earth was destroyed. Rani and Clyde saw the Graske bossing the last of the humans as they were mining, The Graske told them to go away. When Rani and Clyde caught the Graske he told them why he needed the box and why he worked for the Trickster. The Graske almost died in his crashing spaceship until the Trickster told him he could live if he had an agreement. The Graske agreed but was tricked and was forced to do whatever the Trickster told him. The Graske sent Rani to Sarah Jane but kept Clyde. When Sarah Jane reversed time and let her parents die the Trickster was defeated. Clyde and the Graske celebrated and Clyde gave the Graske the box. The Graske couldn't be detected by the Trickster and he was saved. He teleported away and wasn't seen again.

The Graske was briefly seen in a bar where Captain Jack Harkness was drinking in with other aliens such as Hath, Slitheen, Judoon and Adipose.

The Graske has appeared in:

The 2005 Christmas Special: Attack of the Graske

The Sarah Jane Adventures Series 1: Whatever happened to Sarah Jane Smith

Doctor Who Music Special: Music of the Spheres

The Sarah Jane Adventures Series 2: The Temptation of Sarah Jane Smith

The 2010 Special: The End of Time Part 2