The Underground Railroad is a powerful exploration of the experiences of slaves in the USA in the first decades of the nineteenth century. It vividly brings to life the brutality of that period in images that will be hard for some readers to stomach.

The history of the real underground railroad has been extensively documented, so the challenge for any author is how to bring the lives of the slaves and those that assisted them to life. Whitehead’s ingenious idea is to conceive of the railroad as a literal, physical underground railroad, with engines and tracks running from the Southern states to the free North.

“The stairs led onto a small platform. The black mouths of the gigantic tunnel opened at either end. It must have been twenty feet tall, walls lined with dark and light colored stones in an alternating pattern. The sheer industry that had made such a project possible. Cora and Caesar noticed the rails. Two steel rails ran the visible length of the tunnel, pinned into the dirt by wooden cross-ties. The steel ran south and north presumably, springing from some inconceivable source and shooting toward a miraculous terminus.”

The story is told by the third-generation slave Cora, who has been born and brought up on a cotton plantation in deep South Georgia. There are one or two chapters narrated by other characters – Cora’s mother Mabel, and the slavecatcher Ridgeway, for example – but Cora’s is the predominant voice. Escape from the plantation is thought to be extremely improbable and dangerous – it is believed (wrongly, as it happens) to have been achieved only once before, and the punishments meted out to anyone who even tries to escape are barbaric in the extreme. Bounty hunters roam the land tracking down escaping slaves and recapturing them even years after their escape. But the advent of a new plantation owner, and the prospect of even more vicious abuse leads Cora to reconsider the escape plans of fellow slave Caesar. Caesar believes he knows how to make contact with a station manager on the fabled underground railroad.

Although their escape is beset with challenges, Cora and Caesar eventually make it to South Carolina, and begin life as free people for the first time in their lives. In this version of American history South Carolina is the site of an enormous and complex social experiment. Here the benevolent state government buys the freedom of slaves and then gives them jobs, medical treatment and social housing. While this seems utopian compared to the bloodthirsty existence on the plantation back in Georgia, there is a sinister element to this approach to the slavery question. Concerned that blacks are beginning to outnumber whites, the State government is sterilising black women and using black men to track the spread of syphilis. This is one of a number of theoretical approaches to slavery and the social problems it caused that are explored in the novel. How could a society dependent on black labour for the basis of its agrarian economy transition to a new model while preserving its prosperity? Although there were forced sterilization programmes across the USA in the twentieth century, evidence of this being an approach to slavery is hard to find. In fact quite the opposite happened – because slaves were so valuable, particularly after restrictions began to be applied to the transatlantic slave trade, female slaves were given fertility treatment to increase the number of children they had. Just to be clear, this is not a criticism of the novel’s exploration of this issue. It is in many ways best seen as an alternative history approach to considering the experience of slavery, even if many of the events described are drawn from real-life testimonies.

Throughout the novel Cora is relentlessly pursued by a bounty hunter named Ridgeway. Ridgeway failed to catch Cora’s mother, Mabel, and is determined to right this wrong by recapturing Cora, whatever the cost. He tracks her to South Carolina where she escapes at the last minute, leaving Caesar behind to be lynched by a mob. She ends up in North Carolina and is offered refuge by the son of a former railroad station operator. North Carolina has a different approach to slavery from its southern neighbour. Seeing the growing black population as a threat, North Carolina has launched what amounts to a holocaust against all black people, together with any who support or shelter them. Slaves have been replaced with mainly Irish indentured servants instead, just one step above slaves themselves. Any black people found in the State, irrespective of their legal status, are summarily executed, with a long series of bodies displayed across the State in a so-called Freedom Trail. (I had to look up whether this was a real thing or not – the brutality of slavery was such that it wouldn’t have surprised me if it was, although it is more an image drawn from Ancient Rome than the American South). Lynching black people has become a ritualised part of North Carolina’s society. Cora hides in the former station-master’s attic for several months, but is once again captured by Ridgeway when her presence is betrayed by the family servant. (The echoes between Cora’s time in the attic and the experiences of Anne Frank are clear, as are the wider points of reference between the slave-owners and the Nazis.)

Ridgeway tries to take Cora back to her owner in Georgia, but en-route she is rescued by some escaped slaves and taken to a free black farming community in Indiana. This is another, more positive alternative to life under slavery. Living on land once stolen from native Americans, freed and runaway slaves supported by abolitionists live in a community of equals.

“The land she tilled and worked had been Indian land. She knew the white men bragged about the efficiency of the massacres, where they killed women and babies, and strangled their futures in the crib. Stolen babies working stolen land. It was an engine that did not stop, its hungry boiler fed with blood.”

But it is clear this success cannot last, threatened from without by worried white neighbours, alarmed at the growing number of people living on the farm, and from within by nervous residents who disagree with the policy of offering sanctuary to runaways. This debate – whether progress in the fight for freedom for slaves can be achieved by radical challenges to the status quo or a gradualist, legal approach – was one of the many discussions in the novel that echoes the issues faced by modern African Americans .

This was a compelling read. The elements of magical realism in the novel, in particular the vision of the railway itself, and the discussions of some of the alternative responses to slavery, blending compellingly realistic descriptions with more fantastical concepts to make a gripping whole. In writing about this shameful period of American history a fine line has to be navigated between under-stating the barbaric nature of the treatment of slaves and exploiting those experiences for their shock value (in the way that, for example, Django Unchained does). Whitehead strikes that balance carefully – he doesn’t look away from some of the distressing scenes, but neither does he linger upon them. His characters are all well-rounded, believable individuals, even Ridgeway the remorseless Ahab-like bounty hunter.