The Loo Sanction by Trevanian

A First-Rate Thriller from a Legendary Master
Jonathan Hemlock, the art professor and mercenary who first excited readers with his daring exploits in The Eiger Sanction, returns in an even more masterful adventure in The Loo Sanction, Trevanian's second thrilling spy novel. Hemlock has gone to England to rest, but his vacation is interrupted when the head of British Intelligence needs his highly skilled services. Jonathan must take over the mission of an agent whose murder was so bizarre and terrifying that no other agent was willing to replace him.
His task: to locate a set of secretly made films that incriminate a number of high-ranking British officials. His target: a top underworld figure who delights in debauchery and torture. Facing this threat, Jonathan is drawn into a labyrinthine network of intrigue and depravity. As all the pieces in the dangerous puzzle begin to come together, Jonathan is trapped, almost fatally drugged, and forced to attempt one of the most daring escapes ever conceived. The Loo Sanction is sure to keep readers frantically turning pages until the thrilling climax.
Also available as an eBook
Look for these other Trevanian classics from Three Rivers Press: Shibumi, The Eiger Sanction, The Main, and The Summer of Katya.