Believing there is something behind the murder, he seeks to uncover the truth and finds an international conspiracy of corrupt bureaucracy and pharmaceutical money.

Justin Quayle, a British diplomat in Nairobi, Kenya, is told that his activist wife, Tessa, was killed while travelling with a doctor friend in a desolate region of Africa.

As he begins to piece together Tessa's final report on the fraudulent drug tests, he learns that the roots of the conspiracy stretch further than he could have imagined; to a German pharmawatch NGO, an African aid station, and, most disturbingly to him, corrupt civil servants in the British Foreign Office.

John le Carré writes in the book's afterword: "by comparison with the reality, my story [is] as tame as a holiday postcard".

[4] In August of 2005, Focus Features released a film adaptation of The Constant Gardener directed by Fernando Meirelles, starring Ralph Fiennes and Rachel Weisz.