What if Edgar Rice Burroughs' planetary romances were correct and Venus and Mars were habitable? What if we discovered that not only was each planet habitable, each planet was inhabited? And these discoveries were made right smack in the middle of the Cold War?
TSP develops the premise by following the actions of Marc Vitrac, an American soldier from Cajun country resident at Jamestown, the American/Commonwealth base on Venus (the Soviets planted the first colony at Cosmograd, a few years earlier). Venus is not only inhabited, it has residents who appear to be homo sapiens, along with Neanderthals and Earth's dinosaurs. These facts, along with a fossil record that cuts off abruptly 200 million years earlier, are driving evolutionary theorists batty.
There's plenty of intrigue between the Cold War rivals (and would-be rivals), run-ins with hostile residents, distressed damsels, storms that make Katrina look like an April drizzle (warmer weather and more oxygen in the atmosphere), and suitably bad bad guys. The climax of the book involves an over-the-top cavalry charge by our hero on a dinosaur which begs for a filming. If you're a fan of sci-fi in-jokes and jabs at current literary culture, you'll find plenty to amuse as well.
Finally, there is a dawning realization that intelligent design may have played a role in Venus' configuration, which helps set up the to-be-released sequel set on Mars, In The Courts Of The Crimson Kings.
In short, if you liked The Peshawar Lancers, you'll get an equally-big kick out of The Sky People.