An adaptation of Raymond Briggs’ children’s classic that mixes live action and CGI animation to follow the adventures of a family of green monsters who live in the slimy underground world of Bogeydom. Fungus and his wife Mildew suspect their son Mould is illicitly dabbling in human culture, sparking a family argument that sees the boy flee to the surface. Above ground in Daventry, Daryl Hedge’s go-getting wife Wendy won’t let him forget it that he is unemployed, while his daughter Lucy has fallen for a disagreeable older boy called Dean.

An unusual explorer named Gum and his kindly niece adopt three orphans — Pauline, Petrova and Posy — and raise them as sisters in 1930s London. But the girls must fend for themselves when Gum doesn’t return from one of his adventures. Together, they nurture their passions for acting, aviation and ballet in this charming TV adaptation of Noel Streatfield’s novel.