Ronnie Corbett, the British actor and comedian recently revealed what alien will be returning for the special Comic Relief episode of The Sarah Jane Adventures. Whilst speaking to The Daily Express, Ronnie confirmed that the returning alien is the Slitheen, and he also revealed that he will play a bowler-hatted ambassador from outer space who visits Sarah Jane's attic. The special episode of The Sarah Jane Adventures is written by Gareth Roberts and Clayton Hickman, and it will air this Friday from 7pm on BBC One as part of Comic Relief night.