A thoroughly engaging serial that moves along at a great pace. The intrigue is set up quickly, and kept me on the edge of my seat throughout. There were enough twists and turns to keep me entertained though the entire serial. Coming so soon after another Cybermen story is a bold move, but they build upon what we have seen before, and dial in the formula that will become a staple for future Cybermen stories. The guest cast is excellent throughout, with special notice to Sally Faulkner as Isobel, and Kevin Stoney as Vaughn.