Adopting for their own the lost bear they find in Paddington Station, the Browns have some exciting first moments with him.

When the Ambassador moves to London, the twelve little girls go to visit his son, Madeline has an adventure on a horse, and the horse returns to Paris with the girls.

When a boy being chased through present-day London seeks refuge in the National Gallery, a dog escapes from the painting of one Dutch master and together they leap into the painting of another, where their adventures in seventeenth-century Delft are a prelude to returning to London and continuing the chase.

When Maisy and her friends visit London, they go on a whirlwind tour of the city on a double-decker bus, a water taxi, and an underground train.