To celebrate 50 years of the celebrated musical film Chitty Chitty Bang Bang, best-selling children's author and die-hard Chitty fan David Walliams attempts a 'fantasmagorical' engineering feat.
Can he make his childhood dream come true, by building a real life Chitty Chitty Bang Bang car, that will actually fly? To help in his madcap plan he enlists a modern day Caratacus Potts, in the form of aeronautical engineer Tony Hoskins, who specialises in attempting the impossible.
Will their combination of imagination and engineering knowhow be able to pull off this Christmas miracle? Along the way, David delves into the history of how Chitty came to be, starting by discovering the real car that inspired the original children's book, written by James Bond author Ian Fleming, right up to its adaption for the big screen by a young writer named Roald Dahl.
To help on his mission, David is joined by a class of eight-year-old primary school children who are putting on a Chitty school play. They help him understand just why it remains one of the most enduring children's movies - from the timeless tunes and magical inventions, to the terrifying child catcher.
Chitty Flies Again with David Walliams airs New Year's Day at 7:30pm on Channel 4.