At the end of Rolling Thunder, the great asteroid starship Rolling Thunder leaves the solar system led by the extended Garcia-Strickland-Broussard clan. The ship is a classic hollow rotating cylinder, propelled to a high fraction of the speed of light by the mysterious squeezer-bubble technology invented by Jubal in Red Thunder. As with previous installments in the series, we again jump forward a generation. The story is told in the first person by identical twins Cassie and Polly, daughters of Jubal and Podkayne. After one of Jubal’s regular exits from stasis in a “black bubble”, he screams that the ship must be stopped. Eventually he figures out that Dark Energy (catchily referred to as “Dark Lightning” in the book) may be a danger when traveling at a very high percentage of the speed of light. However as always with Varley, the story is about the people. Jubal’s scream of “Stop the Ship!” triggers shipwide unrest, and the twins are the ones who have to sort things out.
In true Varley form, the worldbuilding is first-class, detailed and intricate. The characters are authentic and easily engage the imagination. The twins are in their late teens, and as such their commentary is peppered with talk of boys and fashion, but without being annoying. Mostly it is just plain funny. After the pessimistic tone of Red Lightning and very gloomy one of Rolling Thunder, it is also nice to read an installment in the series with a brighter outlook.