The Klepton Parasites (comic story)

Summary
On Earth, John and Gillian meet their grandfather, the Doctor. They travel in the TARDIS to the 30th century, where the Kleptons are attacking the peaceful Thains. The travelers help them repel the invaders, follow the Kleptons to their secret undersea base, and defeat their plans.

Characters
The Doctor's grandchildren John and Gillian only appeared in comics.

Continuity
to be added