The book centers on a translation of the two essays on Zen and the sword by the Zen master Takuan Sh (1573-1645), Record of the Marvelous Power of Immovable Wisdom (Fudchi shinmyroku) and Record of the Great Primordial (Tai-a ki). Included is an introduction describing the master's approach to Zen in the sword essays that draws on several of his other writings; and a discussion of the related ideas presented in Art of the Sword (Heih kadensho), the classic by the shogun's fencing instructor and Takuan's Zen student Yagy Munenori (1571-1646), for whom Record of Immovable Wisdom was composed. This is followed by a biography of Takuan that lends the translation some historical context and draws on Takuan's surviving correspondence, along with the traditional biographies by the master's student Takeno Munetomo and other contemporary documents.