This American debut takes the form of a diary that charts three weeks on an overcrowded vessel salvaged from the wreck of a transatlantic liner on the eve of the First World War. Grace, the diary’s author, stands accused with two other women of murdering Hardie, the gruff sailor who ruthlessly manages their bid for survival by periodically inviting “volunteers” to disembark from the leaky lifeboat. Charlotte Rogan seeks to generate a sense of dread from a dire predicament while presenting a between-the-lines portrait of her protagonist. These aims cancel each other out: the novel asks you to care about a character whose life it would for the purpose of mystery conceal. However pungent the haze of paranoia – as survivors wonder who will be next to die – the lack of definition to Grace lowers the stakes attached to the ever-present jeopardy. Grace does hint that she deliberately snared her husband (a rich banker lost with the ship), which leads us to suspect she isn’t as innocent as she makes out. The novel is blunt about its vagueness on this point, which sounds like a contradiction, but if I tell you that a fellow survivor for some reason sees fit to give Grace a quick gloss on Freud’s theory of repression, you get the idea. Her diary, written in retrospect on the advice of a lawyer, seems to hide as much as it reveals: more than once she says she briefly fell asleep and woke to hear only the last words of a plan hatched by her co-defendants. But then Grace is often hard to believe, implausible as well as unreliable. Marine similes adorn her prose (she mentions an idea “sneaking into the strongbox of my thinking like water through an uncaulked chink”) and she likes a schlocky cliffhanger. You could see The Lifeboat as an allegory of female self-determination under patriarchy. Squint hard enough and there’s one about US foreign policy, too. At Grace’s trial, the court hears that Hardie’s death is like “the overthrow of a malevolent ruler, a despot… a tyrannical autocrat who was endangering the lives of people in his charge”. Rogan began the novel 10 years ago. The epigraph comes from a Mesopotamian myth; Grace’s initials are, for what it’s worth, GW. Can murder ever be moral? On such questions book clubs thrive, or so publishers hope.