Hi-de-Hi! was set at Maplins, a holiday camp owned by entrepreneur Joe Maplin in the fictional seaside town of Crimpton-on-Sea, Essex. It is loosely based on Butlins, the holiday camp empire of Billy Butlin, his Redcoats replaced with 'Yellowcoats'. At the end of the 1958 season, the camp Entertainment Manager Mr Baverstock, a conman and womaniser, had been sacked for stealing charity money from the camp wishing well. At the same time, the camp comic Teddy Drinkwater had burned out and resigned, leaving the two posts vacant. The following year, a Cambridge University Professor of Archaeology, Jeffrey Fairbrother, tired of academia and applied for the role of Entertainment Manager. This annoyed the portly Camp Host, Ted Bovis, who wanted the job. The job of Camp Comic was given to naive but kind-hearted Spike Dixon, who is awaiting his 'big break' and wants an introduction to the world of show business.
Most episodes involved Ted Bovis attempting to scam the campers as well as the well-meaning Fairbrother, who also had to avoid the romantic approaches of Chief Yellowcoat and Sports Organiser, Gladys Pugh, as he was estranged from his wife but was initially reluctant to divorce her because of the social stigma attached. Most of the other characters in the show were out-of-work actors and entertainers at the tail-end of their careers. These consisted of Fred Quilley, a disqualified jockey; Yvonne and Barry Stuart-Hargreaves, two former ballroom champions and Mr Partridge, a failed Music Hall star reduced to performing Punch and Judy puppet shows for the children. All these characters were big stars in their prime, but were forced to take jobs at Maplins to due their careers failing, most of which were due to the chaos ensued by the aftermath of the Second World War. Other characters consisted of several young men and women who had summer jobs as Yellowcoats, and Peggy Ollerenshaw, an eccentric but ambitious chalet maid who dreamed of becoming a Yellowcoat.