Chaos Pool

The Chaos Pool was the place in which the Key to Time was forged and where it could be destroyed without affecting the whole of the universe. When in human form, it took the name of Pool.

It was located on the planet Chaos, though the Fifth Doctor, Zara (with Amy concealed within her satchel), Astra, Captain Pargrave and Lydel had to search for it on the planet's surface. When the Key was complete, the Doctor took it with the Grace inside, who were still waiting for the Key to be released to them, and jumped into the Chaos Pool to destroy it. The pool vanished, making Romana, Zara and Amy temporarily think the Doctor was dead, but he was actually stuck on a ledge in the pit the pool left behind. (AUDIO: The Chaos Pool)

"Pool" later came to find Abby and Zara on behalf of the Grace to stop a problem with a fusion reactor. Zara decided to help her. He tried to persuade Dodyk to forget the experience and then transported away. (AUDIO: The Bomb)

He appeared on Spacedock 10 to tell him that he knew that they would absorb the power of the reactor. He was a construct of the Grace and that they depended on their help. (AUDIO: The Ward)

Pool took Abby and Zara to the end of time to a ballroom. He was drained taking him there.

He asked Marcella what she would do when he told her what Abby and Zara would be. He also asked Chaff and Gutierrez what to do. He later returned Annie's memories to her to ask her what they had told her.

He wanted Abby and Zara to help him and wanted to change Triangle's opinion. The more he asked people on what to do the less he knew the decision. He was the Chaos Pool in human form as he wanted to know what Abby and Zara have experienced. The Grace told him to question everyone about Abby and Zara. They told him that he need to experience more. He died for Abby and Zara to live. (AUDIO: The Dance)