Liverpool, 1752: a debt-ridden merchant commissions a slave ship to save his fortune and his son's marriage prospects, sending his nephew Matthew Paris aboard as ship's surgeon. As the Liverpool Merchant sails the triangular trade, tension mounts between a ruthless captain and a cousin torn by conscience—setting cousins Erasmus Kemp and Paris on a collision course that spans decades.
Traders who flood a society with cheap manufactured goods it never needed wreck its own industries and make it dependent on trade. To keep buying, that society must supply what the traders want, which here means capturing its own people, and it needs ever more guns to do it. So the outsiders get the dirty work done by others while they stay on the edges.
Being made to suffer does not stop a person from making others suffer; it shows them how. Hardship passes downward, and those who are brutalised learn the methods of brutality.
A trade that the law permits feels morally settled to those who profit from it, however much death it spreads. 'The trade is lawful, they say, and that is enough' lets people shut out the human cost, and the sheer size of the profits makes the legal cover feel even firmer.
Once the pursuit of money is treated as sacred, any means used to get it becomes a duty rather than a crime. A debtor turns into a walking investment who can be worked to death or sold, and no one calls it cruelty, because they are only recovering what is owed.
A person can live and die believing they are someone they are not, simply because nothing ever forced them to find out. Only extreme circumstances reveal true character. Since character is shaped by what happens to people, a change in conditions can also change what they are.