Death in Paradise season 15, episode 1 cast includes Gavin & Stacey and Waterloo Road starsWho guest stars in season 15 of Death in Paradise? Here's the complete roster of guest stars appearing in series 15, episode 1 of Death in Paradise. Steffan Rhodri plays George McCannView 6 Images Steffan Rhodri guest stars as George McCann (Image: BBC)‌Gavin & Stacey star Steffan Rhodri portrays George McCann. Louis Davison plays Leo QuinnView 6 Images Louis Davison guest stars as Leo Quinn in season 15 (Image: BBC)Louis assumes the role of Leo Quinn. BBC Death in Paradise season 15 airs on BBC One and BBC iPlayer at 9pm on Friday, January 30.