The Scottish Prisoner, by Diana Gabaldon

Hmm, I need to reread the "Companion" to see how this fits in and to figure out...a bunch of stuff. Anyway, this is about Lord John and Jamie going to Ireland to stop an Irish plot to restart the rebellion that ended at Culloden. A bit silly, but the story is less important than John and Jamie equalizing their relationship. This is also prior to John's marriage, so Jamie is still living at Helwater as the (paroled) prisoner of the title.