Super-twisty, with a very complicated timeline, this one is a great entry in the River Song story. This time out, and I think for the first time on the Big Finish River Song episodes, we have a box set that is one big story! Must say the authors really pull out all the stops. So far it's been one of my favorite Big Finish productions to date. I suggest starting this one when you have time to listen to the discs in quick succession, say over a day or two. I'm digging into disc 4 this afternoon.