A Letter of Mary is the third in the Mary Russell mystery series of novels by Laurie R. King. This is the first case that Mary Russell and Sherlock Holmes work on together as husband and wife. The story features a cameo by Lord Peter Wimsey. Plot summary In August 1923, Mary Russell and husband Sherlock Holmes receive an unexpected visit from Dorothy Ruskin, an elderly amateur archeologist from the Holy Land, who met the couple four and a half years earlier during the events from O Jerusalem (novel). As a gift, Ruskin presents Russell with an inlaid box containing a papyrus scroll, which seems to be a genuine first-century letter by Mary Magdalene. When she returns to London that evening, Ruskin is killed in a hit-and-run accident with only two witnesses. When Holmes and Russell visit London to identify the body, they discover evidence of foul play. Before her murder, Ruskin had argued with a sponsor of the digs, Colonel Dennis Edwards. A letter from her sister Mrs. Erica Rogers, who cares for their aged mother, reveals that two Middle Eastern visitors were also looking for Ruskin after her visit home. Finally, Holmes and Russell find their Sussex home ransacked by three suspects who were looking for papers, perhaps for Mary’s papyrus scroll. When Russell translates Mary’s letter, she finds that Mary calls herself an apostle of Jesus, and contemplates the theological and historical implications. Three distinct suspects and possibilities emerge: Colonel Edwards, who did not know he was sponsoring a woman’s project, could have been enraged to violence; the Middle Eastern visitors may have been from a Palestinian family with a grudge against Ruskin; and Rogers was resentful toward her sister, though according to Ruskin’s will, she does not benefit from Ruskin’s early death. To pursue each different line of investigation, the four split their forces: Mycroft Holmes looks into the Middle Eastern visitors, Holmes goes into Erica Rogers’s employ, while Inspector Lestrade directs the efforts of the police, and Russell finds work as Colonel Edwards’s secretary. In Colonel Edwards’s employ, Russell grows to like the colonel but is repelled by his misogyny as well as Gerald, his lecherous son. She also finds strong evidence of the colonel's antagonism against Ruskin, but nothing more incriminating. After a week of investigations, Russell, Mycroft, and Lestrade have little to show, but Holmes has succeeded in finding parts of the car