When unexpected debris from outer space crashes onto their peaceful planet, the Clangers explore these strange arrivals with curiosity and wonder. Among the scattered objects, a hoot, a trumpet-like creature, falls into one of the Clangers' caves. Small and Tiny Clanger swiftly pull the poor hoot to safety.

The Hoot Planet comes to retrieve the missing hoot, but Tiny's pipe organ chimes in wishing to go with the hoots. As Tiny attaches the pipe organ to the planet, the Hoot Planet recklessly takes off hoisting Tiny into space.

Frantically rushing after her, Small and Major Clanger save her. On their way back home, the Clangers and the Hoot Planet encounter glorious celestial instruments playing lovely music.