Moving back and forth between 1989 and 2020, this tells two intertwined stories. First is how Lachlan Kite is recruited at an elite boarding school into Box 88 and send on a mission to France in investigate an Iranian's connection with the Lockerbie bombing. Second is in the present as MI5 hears rumors of Box 88 and starts to investigate Kite even as Iranian intelligence moves against him as well.