Gerry and Sylvia look back on the circumstances surrounding the series' creation and the way in which many of the show's most popular characters and features were dreamt up. From Lady Penelope to Brains and from the the famous rescue vehicles to a menacing villain, this anniversary celebration shows how all of the elements initially came together. Alongside the series' co-creators 'Thunderbirds Are 60' also features interviews with writers Alan Pattillo, Dennis Spooner, Alan Fennell, and Donald Robertson – who describe the challenges of writing for puppets.