David contributed games to 'The Crystal Maze', and is a full-time format consultant, producer, games devisor and question writer/editor. He has worked on iconic TV shows such as ‘The Krypton Factor’, ‘Treasure Hunt’ and ‘Fifteen to One’. He was also question editor for the first eight series of ‘Only Connect’. His experience covers TV, radio, websites, on-line gaming, 'red button', advertising campaigns, board games, live events, interactive formats and print. He is the author of over 60 puzzle books, and is a two-time winner of the World Creative Thinking Championships (yes, that’s a thing).

Justin is a BAFTA-award winning global content specialist, format creator and trainer with 30 years’ experience, known internationally as The Format Doctor. Justin has created hit formats including ‘Chef In your Ear’ (13 territories), ‘Codex’ (Channel 4), ‘Shock Treatment’ (Sky) and ‘Starfinder’ (ITV). Justin also co-developed ‘Doctors Vs Internet’ (NRK), ‘Splatalot’, ‘Canada’s Smartest Person’, Discovery’s ‘Know It All’, and ‘Sing My Song’ (China/CCTV) which averaged 252m viewers per season. Justin is a visiting lecturer, keynote speaker at media festivals and author of 11 books.