SID SMITH WRITES fascinating novels for part of the way. Then something happens. His first novel, Something like a House, is about a British soldier who wanders away from the Korean War and ends up in a remote region of China, where he melts into a non-Han community. It is a unique setting and the soldier, although virtually mute, makes a memorable central figure. In the novel's second half Smith gets a bee in his bonnet about local and international politics, the story dwindles, and so did my interest, although the book won the Whitbread Prize for first novels and the James Tait Black Memorial Prize.

Now, in A House by the River, which the publisher describes bafflingly as a 'prequel' to the earlier novel, Smith tells another bizarre but riveting story, also set in a remote southern region of China in the early twentieth century, about the missionaries John and Grace. Neither of them fits