A gaseous alien arrives on Earth to warn people to evacuate before its race invades. It attempts to communicate with humans telepathically, but they disregard his warning as madness or a trick. Convinced that the humans' lack of fear is due to some impenetrable defence, the alien leaves and warns its people to call off the invasion.; A man descends in a bathysphere into a pit so deep that he is surprised to find a waterless cavern beneath it occupied by elves banished long ago by a wizard. They stole the magic ball that kept Atlantis safe from the waves and so a sorcerer cast a spell that would send them to the deepest pit in the Earth. They offer to make the man ruler of humans if he returns them to the surface would. He agrees, but then has second thoughts about unleashing their mischief upon unsuspecting humanity and destroys the bathysphere, accepting underground exile in the process.; A man spends twenty years building a time machine in order to use knowledge of the future to enrich himself. He travels to 2010 and memorizes stock market and horse race information from the newspaper archives. When he tries to return to the past, however, he finds that he accidentally left his time machine in a futuristic garbage processor, and it has been disintegrated.; Certain that the world will soon descend into nuclear war, a brilliant scientist goes into cryogenic suspension for a million years, hoping to awaken in a more enlightened time. Instead the world quickly retreats from war and advances rapidly. By the time he awakens, most humans have left Earth, and the few remaining are being rounded up to serve as conscripted soldiers in an alien war.; An aging space pilot is mocked for his slow ship, but when an invading armada approaches Earth his ship is the first to see it. His warning allows Earth to beat back the invasion, making him a hero and the commander of a new space patrol.; The 5th dimension is the dream dimension. The creatures there are trying to pass into this dimension, but belief in their existence as opposed to surmising a mere dream experience disrupts the structure of the dream dimension and forces the creatures to withdraw from our world. The narrator sells his story to Strange Tales to encourage readers to believe in the creatures and frustrate their invasion aspirations.; A short lab assistant works on a growth serum to gain a normal man's height. The serum works too well, and he continues to grow so tall his life is endangered when the air becomes too thin to breathe. Just as he is about to black out, the serum wears off, and he is restored to his original height having learned to be satisfied with the way he is.; Aliens from the planet Regulus colonize Earth, treating humans as little more than animals. They must withdraw only because of their vulnerability to Earth's germs.; Two scientists try to travel to the future, but arrive in the stone age. They believe they have proved travel into the future impossible, not suspecting that they actually saw the world after the destruction of civilization by war.; An old eccentric in a wheelchair hires a sea captain to take him to a spot where he believes that the lost continent of Atlantis lies. When they reach their destination he reveals himself to be a merman and thanks the sailors for bringing him home before diving overboard.