The novel “If Tomorrow Comes” by Nancy Kress was published for the first time in 2018. It’s the second book in the Yesterday’s Kin trilogy and follows “Tomorrow’s Kin”.

The starship Friendship has reached the planet Kindred, also called simply World, the Denebs’ home. Onboard, in addition to the crew, there are scientists and diplomats protected by a team of rangers. They expect to work together with an advanced civilization, but the only other starship they find in the area is Russian, arrived only to destroy World’s civilization and the Friendship, and then return to Earth.

A shuttle from the Friendship manages to escape the Russian attack and land on World, where the Earthlings find a low-tech civilization capable of building a starship only thanks to the instructions left by whoever brought the Denebs to World many millennia before. The natives don’t have enough scientific knowledge to discover a vaccine that will protect them from the lethal spores that will soon hit the planet.