Book excerpt: Most conversion books contain multiple stories. One Shepherd, One Flock contains one, and it's like no other. The first part is taken from the diary Oliver Barres kept before becoming Catholic. You travel with him from disagreement to assent--no other conversion story can match this. The second part defends the Catholic beliefs Barres once found indefensible. With an introduction by Frank Sheed, a foreword by Avery Cardinal Dulles, and a preface by Fr. Benedict Groeschel.