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Kestral was head of the Silurian tribe that locked onto the Lucy Gray.

The Eleventh Doctor and Amy Pond helped Kestral and Seelac to protect their space ship against an asteroid storm.

When Kestral and Seelac met the humans on the space ship they tried to take the Doctor and Amy as a hostage to force the humans to work for them. However Captain Roy Calvert told them that the Doctor and Amy were strangers to them and that he wouldn't put his people in slavery for them.

Together with Amy the Doctor convinced Seelac and Kestral to work together with the humans and sail together through space. Seelac, Kestral, Tina Lockheart and Captain Calvert shook hands and made peace.

Only seconds after that a Dalek space shuttle crashed on the SS Lucy Gray. The Silurian space ship fell down back to Earth, together with all Silurians. The Doctor managed to talk to Kestral, who told him that he and his people were okay and that they would find a way to survive. Furthermore he mentioned that a friendship between humans and Silurians wasn't meant to be. The Doctor told him that there would be another time when a friendship would be possible. (GAME: Evacuation Earth)

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