It is now six million years into the future, the galaxy is relatively stable and the shatterlings are preparing for their 32nd reunion, at which they collate their knowledge and experiences, make major decisions and tell of the misbehaving clones, when disaster strikes!! Someone has launched an ambush on the Gentian line and all but wiped them out! OMG.
Campions and Purslane are late to the reunion (by several decades) because they travel together - a serious breach of the Lines rules. Worse still, they are lovers, which is entirely unacceptable to the Line. It all worked out for the best though, because now they can find out the answers to the real questions at hand: Who wants the Gentian Line dead? And why?
I wish that this were a series rather than a standalone novel. The Lines are such a fantastic idea, families of identical people with identical memories, living over millions of years, watching the galaxy develop, watching civilisations and empires rise and collapse, seeing the path that real time humanity takes in all it's branches.
Reynolds stories are written with the assumption that FTL is not possible. This makes for fairly boring space combat on the surface, but Reynolds manages to convey a thrilling visual image with an understanding of the reality of moving through space at sublight speeds. That doesn't really make sense now that I re-read that sentence, but I know what I mean.
Probably the best Reynolds story since the Merlins Gun shorts a few years back. Highly recommended.