In her engaging biography, Katherine Rundell considers the life of the poet John Donne (1572-1631) as one of serial metamorphosis. The approach suits him well, given Donne’s fascination with instability, and the fact that events forced him to keep on adapting. He was born to a Catholic family during the Elizabethan persecution, which left either recusancy or compliance open to him. He chose the latter, and a long future of shape-shifting awaited. Trials of conscience proved as demanding as those of circumstance: in some respects, Donne’s work is a record of this struggle, from the secular verse of early maturity to his sermons, eventually as Dean of St Paul’s.