After sleeping for some time below one of the Earth's oceans, an earthquake opened up the crust of the planet, and Godzilla, awakened by the event, travelled to the surface of the ocean to find himself somehow once again in the time of Dinosaurs, essentially returning to the time period in which he had lived before being mutated. The Stranger was a Kaiju that had come to Earth from somewhere in Space, looking for both food and combat. After attacking a nearby Triceratops and devouring it, the Stranger noticed Godzilla, who had begun wandering the land mass on which the Stranger was hunting prey. Realizing that Godzilla was the challenge it was looking for Stranger attacked the Kaiju. While the two monsters grappled with one another they failed to notice a large asteroid streaking towards them.
Eventually the asteroid struck the ground, the Stranger attempted to flee the destruction wrought by the asteroids impact, having a portion of its tail torn off by Godzilla in the process. As the Stranger fled, Godzilla was caught in another earthquake, which sent him plummeting down a massive schism opened by the quake, where he apparently collapsed due to exhaustion.
When Godzilla awoke he once again found himself in his proper time period. At first it seemed the entire battle with Stranger was simply a dream, until Godzilla looked downward and saw he was clutching the severed tail of the Stranger.
It is possible the Stranger was of alien origin, or at least was an undiscovered species of dinosaur. Text captions seen throughout the story, however indicated that the Stranger was indeed of extraterrestrial origin, first claiming that it had come to Earth seeking food and challenge, and then once the asteroid hit, that it was attempting to flee back into space. Whether or not the Stranger successfully escaped Earth is unknown. The final panel in which it appears is ambiguous, as the creature is seen attempting to escape Earth as the shockwave from the asteroid impact began to sweep the globe, leaving the fate of the Stranger up to the reader.