Mary, Mungo and Midge notice a crane outside and the two animals go on an adventure inside.
Mary allows Mungo and Midge to post a letter for her to Grandma but Midge falls inside the letterbox and goes on a wild journey.
Midge sails Mary's boat in the pond.
Mary and Mungo are printing and then go to the shops, whilst Midge travels with them to a printing factory.
Midge breaks the clock in the hall so men are hired to fix it, whilst he climbs aboard.
Mungo thought he could go and see Mary where she went to see her aunt who had just moved to a new house, but Mungo got really lost so he decided to ask a policeman to take him home while Midge was looking for him.
Midge wonders where cows fit in the machine, but he causes chaos with all the milk coming out of the machine.
Midge climbs inside Mary's broken doll when she and Mungo go to the toy-shop for it to be mended.
The family go to the funfair.
Midge flies in a balloon in the park whilst Mary flies her kite.
Midge is left in the garage whilst the rest of the family go into the country for a picnic.
Midge secretly follows Mary into the hospital after she injures her leg.
The family go to the seaside and Mary, Mungo and Midge go their separate ways. Midge goes to sleep with his flute.