Hammy wanders far from home and meets Martha Mouse, who takes him to see Turtle, the Wise Old Frog and GP the Guinea Pig.

Hammy spots an old boot floating down the river and decides it would make a wonderful place to live. GP uses his amazing new invention to help, and everybody pitches in to build a home for Hammy.

Hammy and Martha get lost in an early morning mist on the river, but GP and Turtle set out to rescue them in GP's balloon.

Hammy, Martha and GP set off on a birdwatching adventure and come to the aid of a squeaking Weathercock.

Martha builds a kite for the annual tug-of-war with the Wind. The contest begins, but Wind catches GP cheating.