One of the reasons it is so good, is that it is actually fairly accurate. Of course it is speculation whether or not Rasputin had an affair with the empress. He also did not simply shrug off being poisoned and died a gruesome death. There is a lot of discussion that the murderers had a lot of interest in upholding the legend of the unkillable man both to legitimize their actions against an unholy being as well as to increase the clout they might get.

But on a very surface level it’s a good retelling of a remarkably odd tale out of history.