From Raxacoricofallapatorius with Love

The gang are talking to Mr Smith when suddenly there is a breach in the attic. Mr Smith identifies the disturbance as a teleport and a diplomat named Ranius (or Rani) (played by Ronnie Corbett) appears. He states that he represents the Galactic Alliance and gives them all gifts for defending the Earth so valiantly. He then pulls up a chair to talk to them and experiences apparent flatulence. Sarah Jane, Clyde, Rani and Luke all notice the similarity of the constant flatulence with that of a Slitheen wearing a skin suit, which Rani denies quite strongly. K-9 materialises and confirms Smith's identification, but Rani states all dogs should be put on a lead and clamps K-9.

After further interrogation Rani immobilises Sarah Jane's, Luke's, Clyde's and Rani's feet using the gifts he had given them and reveals himself to be a Slitheen after all, unzipping his forehead to reveal a diminutive Raxacoricofallapatorian and stating his plan to steal K-9 and the information it contains. Thinking swiftly, Sarah Jane manages to use her sonic lipstick to release their feet clamps and clamp Rani's feet. Clyde then throws Rani's bowler hat at a switch on Mr Smith, teleporting Rani away and releasing the clamp on K-9.