In Rules of Engagement, Sir John and Jeremy are confronted with a series of bizarre deaths on the streets of Georgian London in a mystery that tests even Sir John's legendary skills of deduction. When Lord Lammermoor, a close personal friend of the Lord Chief Justice's, plunges to his death from the heights of Westminster Bridge in front of a dozen witnesses, suicide is ruled as the most likely cause of death. But Lammermoor's fatal leap coincides with the arrival of Dr. Goldsworthy, a student of the famous Dr. Anton Mesmer and his studies in animal magnetism. Sir John's suspicions are piqued when it is discovered that Goldsworthy's patron in London is none other than the beautiful and austere Lady Lammermoor. Meanwhile, Jeremy's sleuthing uncovers a web of intrigue within the ranks of the Lammermoor family, and the deeper he investigates, the more suspects he uncovers who stand to gain from Lammermoor's death.