Justin Moorhouse, Emmanuel Sonubi and Holly Walsh join for an 'upsadaisy' episode.

Tom Allen, Chris McCausland and Lou Sanders look at a range of unrelated 'U' topics.

Sandi and Alan look at some 'U' animals with Rhod Gilbert, Lara Ricote and Ahir Shah.

Sandi and Alan take a look at ufology with Cally Beaton, Nish Kumar and Tom Ward.

Jordan Gray, Jason Manford, Sara Pascoe join an ultra-interesting episode of QI.

Kemah Bob, Alex Edelman and David Mitchell look at the UK-US special relationship.

Gyles Brandreth, Judi Love and Kiri Pritchard-McLean take on an Unsavoury episode of QI.

Nabil Abdulrashid, Bill Bailey, Victoria Coren Mitchell are all in it together.

Aisling Bea, Urzila Carlson and Romesh Ranganathan compete in this upside-down episode.

Sandi and Alan are joined by Eshaan Akbar, Jo Brand and Jimmy Carr for a festive special.

Sandi goes tricking and treating with Ria Lina, Eshaan Akbar, Jimmy Carr and Alan Davies.

Sandi has a testing time with Susan Calman, Maisie Adam, Josh Widdicombe and Alan Davies.

Nish Kumar, Mark Steel and Suzi Ruffell join Sandi and Alan for some thrill and spills.

Zoe Lyons, Greg James and Richard Osman celebrate the hundredth birthday of the BBC.

Hannah Waddingham, Desiree Burch and Jason Manford look at animals that begin with a ‘T’.

Sandi shares tips and tools with Joe Lycett, Holly Walsh, Bill Bailey and Alan Davies.

Sandi Toksvig takes tea with Rosie Jones, Ahir Shah, Henning Wehn and Alan Davies.

Bridget Christie, Sara Pascoe and Deborah Frances White take a look at tubes and tubas.

Jo Brand, Guz Khan and Sally Phillips talk through a tantalising trunkful of 'T' topics.

Sandi goes trundling along with Tom Allen, Cariad Lloyd, Jamie MacDonald and Alan Davies.

Sandi looks at tails (and tales) with Rob Beckett, Daliso Chaponda and Sarah Millican.

Sandi and Alan come over all theatrical with Ed Byrne, Cally Beaton and Jack Dee.

Sandi plays tic-tac-toe with Rose Matafeo, Lou Sanders, Ross Noble and Alan Davies.

Sandi Toksvig hosts this year's QI Christmas special.

With Aisling Bea, Chris McCausland, Gyles Brandreth and Alan Davies.