If you think you know what a Quentin Blake drawing looks like, head for the final room of this small and perfectly formed show (a free gift for Christmas and half-term outings for children, and a pleasure for adults) and enjoy the sketches of women reading for a Camberwell Press limited edition book, and the birds drawn with quills made from their own feathers (including turkeys, who seem particularly miserable).
A glimpse of work in progress comes in a short film of Blake working on this year's picture book, Mrs Armitage, Queen of the Road - with a rare chance to watch characters taking shape.
In the Roald Dahl room, the myths behind the books come to life: I have heard the story of Dahl posting his collaborator the BFG's sandal, but the footwear is bigger than I could have imagined and looks as if the giant designed it himself.
Material on Blake's early career - starting with the 1949 Punch cartoon that appeared while he was still at school, and the first illustrations for children in John Yeoman's A Drink of Water (1960, pictured) - includes Spectator covers, 1960s Penguin jackets, a first-night sketch of Laurence Olivier and family portraits.
A tiny taster of the vast Blake archive, but entertainment in BFG-sized portions.
Quentin Blake: fifty years of illustration is at The Gilbert Collection, South Building, Somerset House, London WC2 until March 28, 2004. Free for under-18s; pound;5 adults (includes admission to permanent collection).
Tel: 020 7420 9400; timed tickets (booking fees) on 0870 906 3702 or www.gilbert-collection.org.uk