We start out in a far future where not only are there aliens, there's several varieties of humans. We have versions of FTL and coldsleep, plus some interesting physics. The three protagonists are Dan Sylveste -- the son of a well-known family who has spent a lot of his life exploring other cultures, Volyova -- one of the leaders of an FTL ship, and Khouri -- an assassin who is hired by a mysterious person to travel on Volyova's ship to kill Sylveste. Things never turn out that easy, of course, and Al gives us ongoing clues to what's happening.
This is a real space opera thriller and I highly recommend it.