It is 1921 & Mary Russell--Sherlock Holmes's brilliant apprentice now an Oxford graduate with a degree in theology
- is on the verge of acquiring a sizable inheritance Independent at last with a passion for divinity & detective work her most baffling mystery may now involve Holmes & the burgeoning of a deeper affection between herself & the retired detective Russell's attentions turn to the New Temple of God & its leader Margery Childe a charismatic suffragette & a mystic whose draw on the young theology scholar is irresistible But when four bluestockings from the Temple turn up dead shortly after changing their wills could sins of a capital nature be afoot? Holmes & Russell investigate as their partnership takes a surprising turn