A classic tale of SF adventure and aliens. Some allusions to the main characters' previous short story adventures. . .
But it opens with Captain David Falkayn, merchant explorer working for Nicholas van Rijn, going to a company called Serendipity that can hook up concepts and yield connections. There, their machinery comes up with a rogue world, not attached to a planet, about to pass by a blue giant and so warm up -- and then cool down as it goes back into interstellar space. This would enable the mass transmutation of elements, since you could build up your process as it cooled, and so dissipate the heat that made it unworkable.
The owners of the company, strange to the Moon and reclusive, want to talk to him. He agrees -- and does not return. His ship mates, the cat-like Chee Lan and the Buddhist dragon-like Adzel, are stymied in every effort, even though the messages from him are not his style at all. So they contact van Rijn.
The rest of the story involves security sophonts from primitive cultures with fierce honor codes, abducted children, kidnapping, hidding on a planet, space chases, much discussion about how biology affects xenopsychology, and much more. Great fun.
Even if the characters don't know why the dinosaurs became extinct. 0:)