Zoe Ball and Jamie Theakston's guests include actor Paul Nicholls , talking about his new police drama series City Central, which begins tonight at 8.10pm, DJ Tony Blackburn, and pop band Ultra, with their latest single Say Va Do. Also mischief from the Leprechauns, comedy from Ben, Gez and Richard, plus Mr Blobby, and cartoon action with the Rugrats and Spiderman.