Imperial Auditor Miles and his wife Ekaterin just want to make it home in time to see their babies born (like most civilised people, they're opting for a replicator birth). However, enroute, Miles is asked to stop and investigate a minor incident - Barrayaran troops have apparently created quite a disruption on Graf Station. Miles' diplomatic authority should be able to calm things down.
However, once he gets there, Miles discovers a thornier problem than expected. The issue isn't just drunk-and-disorderly troops, but a host of intertwining issues involving theft, smuggling, a host of political difficulties, any number of suspicious characters, and a chain of connections that may put the peace of the entire Barrayaran Empire at risk.
I'm not reading these in order, at all, but before reading this one, at the very least, you should've read 'Cetaganda' - I'm glad that I had.