Barker specializes in the sharp detail, the telling observation, the scene so convincing we can’t pull back. When Dr. William Rivers, one of her two main characters, cures a soldier’s hysterical paralysis by drawing a stocking top on his thigh – as the line moves down, sensation gets restored – the “flabby skin kept snagging the pencil point.” The other main character, the anomic Lt. Billy Prior, sees a comrade weep over a patriotic song and writes in his diary, “I envied him.” One repulsively evocative battle scene ends with sleep-deprived soldiers watching in horror as the sun they thought was setting rises. Barker’s early novels are contemporary but this bygone world feels fight, thanks to her academic training in history and to a novelist’s hermaphroditic empathy.

So what’s the “but”? The predictable pitfalls of the historical novel: overwrought design and underdeveloped character. The real W.H.R. Rivers did live among former headhunters in Melanesia before he treated shell-shock victims in Scotland. What novelist could resist milking the parallels – and what novelist could avoid making it seem artificially contrived? One of Rivers’s real patients, the real poet Wilfred Owen, might as well be named John Smith for all we get to know about him. And the imaginary Billy Prior, bisexual and alienated from his (and everybody else’s) social class, is more an alienated Everyman than a person we’re sorry to see the last of. For characters and readers alike, the Armistice comes just a little too late.