An excellent show with a stellar cast, however I can't help but think how similar the plot is in many aspects to John Collee's " A Paper Mask" where a hospital orderly in this case assumes the identity of his best mate, a recently qualified doctor and who perishes in a motor accident. The impersonator goes on to leave a train wreck of a hospital behind. Throughout the book and as I imagine it will be throughout this TV series, you are left wondering when they are going to be uncovered and also with whom they share their secret, generally a lover.