George Weigel is the foremost biographer of John Paul II. In "God's Choice: Pope Benedict XVI and the Future of the Catholic Church", he manages in the first hundred pages to chronicle the close of John Paul's life. Joseph Ratzinger, who would become his successor, Benedict XVI, was one of the facile minds that worked behind the papal throne.
The aging Ratzinger frequently requested retirement, but John Paul II was loth to let him go. Thus he stayed on to help maintain stability in the church. Besides chronicling the physical decline and death of John Paul II, Weigel goes on to assess the state in which he left the church. Weigel notes its strengthened moral position, but is somewhat critical of its bloated bureaucracy. The story behind the conclave that elected Ratzinger to the papacy is told with interesting details. Ratzinger himself delivered a homily to the College of Cardinals that proved somewhat controversial, but spelled out to his fellow clerics exactly where he would lead the church if elected.
Weigel goes on to describe Benedict XVI, personality, background and philosophy. Then he turns to what the elevation of Ratzinger could bring to the church. In his conclusion he indicates his hopes and delivers some well-meaning and perceptive advice based on long study and analysis of the Catholic Church and its leaders.