Ngaio Marsh’s bestselling and ingenious third novel remains one of the most popular pieces of crime fiction of all time.Sir John Phillips, the Harley Street surgeon, and his beautiful nurse Jane Harden are almost too nervous to operate. The emergency case on the table before them is the Home Secretary – and they both have very good, personal reasons to wish him dead.Within hours he does die, although the operation itself was a complete success, and Chief Detective Inspector Alleyn must find out why…