A giant meteoroid approaches the Earth, spotted from an observatory by Professor Calculus, and he and a self-proclaimed prophet, Philippulus, predicts the meteoroid will hit Earth and cause the end of the world. The meteoroid misses Earth, but a fragment of it plunges into the Arctic Ocean. Calculus determined that the object is made of a new material arranges an expedition to find it with Tintin, Haddock and Detectives Thompson and Thomson.

Tintin and Haddock are invited by Professor Calculus at the space center in Central Europe. While visiting, dog Snowy gets trapped in a Moon-bound rocket. It's up to Calculus to build a space rocket for humans to rescue Snowy.

Tintin gets more than he bargained for when he buys a model of a sailing ship for Capt. Haddock that the seaman finds is unexpectedly familiar.

Tintin and the Captain search for the pirate's treasure they learned about the last story ("The Secret of the Unicorn"), with the help of their eccentric, but lovable friend, Professor Calculus

When Tintin is shot by the pilot of downed plane, he and Captain Haddock, travel to Britain to uncover a sinister plot.