Against his better judgment, Geralt accompanies Jaskier to a royal ball. Ciri wanders into an enchanted forest. Yennefer tries to protect her charges.

In the face of uncertainty, Sam turns to Joanna. Elsewhere, a promising new beginning pushes Nellie to her limits.

While Kathy oversees the excavation of Marie's grave, Daniel gives McKinven the lead he needs to make an arrest. But it's the exacting forensic science that finally brings peace for Emma.

Scrooge is confronted with another spirit, which has assumed a familiar form drawn from his own tortured past. He witnesses the present day, and the seemingly happy Christmas enjoyed by the Cratchit family - but also learns there are cracks beneath the surface which he is responsible for making. The final ghost arrives to give Scrooge a glimpse of what the future holds - and a tragedy that will force him to confront the consequences of his misdeeds.

Sandi Toksvig hosts the seasonal quizmas quiz, with Alan Davies, Sara Pascoe, Johnny Vegas and Josh Widdicombe.

The host welcomes another batch of celebrity guests to his famous green room for a special Christmas edition of the talk show. He is joined by David Tennant, whose demonic role in Terry Pratchett and Neil Gaiman's Good Omens will be coming to BBC in the new year, as well as singers Rita Ora and Jamie Cullum, former X Factor judge Sharon Osbourne, Strictly Come Dancing: It Takes Two presenter Rylan Clark-Neal, award-winning Hollywood star David Oyelowo and comedian Bec Hill.