An expedition has a limited opportunity to examine the visitor in Rendezvous with Rama. The object crossing the Solar System is an alien spacecraft, cylindrical in shape and fifty kilometres long. Arthur C. Clarke makes the investigation of that enormous structure the starting point of the novel.

Exploring the interior

Once inside, the explorers encounter a world contained within the ship. Rama's immense scale and unfamiliar surroundings become the substance of the expedition, extending the initial question of what has arrived into the task of discovering what lies within it.