When 133 African prisoners are thrown overboard from a slave ship in suspicious circumstances, Garrow challenges the brutal trade that regards slaves as cargo. It is a case that amounts to a declaration of war.

Returning from war, weary and wounded, British sailors are treated with contempt and abuse at the Greenwich Hospital. One man bravely exposes the corruption, and finds himself in a Newgate cell. Southouse accuses Garrow of mixed motives as his uses the case to attack The Admiralty - and in particular its Under Secretary, Sir Arthur Hill.

Having failed to save a twelve year old mute boy from the gallows,Garrow enters the civil court to hear Hill's accusation of adultery against him in a deeply depressed mood,despite Sarah's assurances. Silvester,previously his adversary,defends him in the spirit of fair play and does well,demolishing Hill's Admiralty cronies,the prosecution witnesses,whilst Mary,Sarah's loyal maid,refuses to perjure herself. However,it is the dogged and devoted Soutouse who saves the day by bringing in a surprise,last minute witness to expose Hill's hypocrisy.