A giant fireball narrowly misses the earth, but a huge fragment of it crashes into the Arctic Ocean. Captain Haddock helms Professor Phostle's expedition to find it and claim it. Bohlwinkel repeatedly tries to sabotage them so that his own expedition can get there first. Thanks to the courage and skill of Tintin, Captain Haddock, and the seaplane pilot, the Phostle expedition wins through.