Yellow alien (The Big, Blue Box)
From Tardis Wiki, the free Doctor Who reference
A species of yellow aliens were from the neighbouring planet to a similar species who they were at war with. They came to Earth to attempt to acquire Douglas Henderson, who was unknowingly a living weapon that could be used to destroy the other species.
However, when Henderson and the Tenth Doctor were teleported to their opposition's ship, Henderson activated himself, disabling both fleets. The Doctor left to tow the aliens back to their homeplanets. (COMIC: The Big, Blue Box)