Series 6: 10. Ricky Martin
Series 4 - Ben Shires
Chat, music and comedy from Hacker T Dog. Hacker tries to keep another show on air, plus his guest is the Officially Amazing Ben Shires.
Series 6: 1. Kimberly Wyatt
Series 4 - Radzi & Lindsey
More flea-bitten fun, chat and music from Hacker T Dog, but what will he make of Blue Peter presenters Radzi and Lindsey?
Series 6: 3. Lauren Layfield
Series 5: 3. Millie & Jeremy
Series 5: 5. Kevin Clifton
Series 4 - Bobby Lockwood
Chat, music and comedy from Hacker T Dog. Hacker tries to outfox Wolfblood's Bobby Lockwood.
Series 6: 9. Paul Martin
Series 6: 8. Luis Troyano
Series 5: 8. Tim Warwood
Series 4 - Sally Nugent
Fun, chat and music from Hacker T Dog, plus another uninvited appearance from Derek's mother. His guest is BBC Breakfast's Sally Nugent.
Series 6: 4. Alison Hammond
Series 2 - Barney Harwood
Blue Peter bloke Barney Harwood finds himself on Hacker's chat show. He's used to appearing on TV, but Hacker Time is not like any other TV show.
Series 3 - Joe Pasquale
More chaotic canine comedy capers from Hacker and his production team, plus there is a familiar face in the Quarter Past Four O'Clock Club. His guest is Joe Pasquale.
Series 5: 2. Maggie Aderin-pocock
Series 6: 2. Leona Vaughan & Louis Payne