In 1807, the British Parliament abolished slavery throughout the Empire. The trade in human misery did not stop, however, as other countries - and illegal slavers - continued to abduct people from the coasts of West Africa. Combining meticulous research with narrative verve, this compelling book tells the story of how, in six decades of dramatic and daring action on the high seas, the Royal Navy's 'Preventative Squadron' liberated 150,000 Africans at the cost of 17,000 of its own men.