Eamon Duffy is well known in the English-speaking world for his studies of late medieval and early Reformation English Church history. His magisterial work The Stripping of the Altars (1992/2005) built on the thesis that Catholicism was very much alive and well in the years prior to Henry VIII's break with Rome in the 1530s and that much of it survived the turmoil of the Tudor successions throughout the mid-16th century until the last dismantlings occurred under the Elizabethan Settlement and then the encroachment of the Puritan movements.
Duffy has also written a recent book on the papacy - Ten Popes that shook the world (2011) - which included a chapter on Pius XII. I bought the book, found it fascinating for the portraits of many of the successors to Peter, but have to confess to feeling somewhat deflated with the chapter on Pius XII. Duffy adds nothing new in what he writes, but he does try to steer a middle course between condemnation and canonisation without resiling from the hard questions, of which the one surrounding "the silence" is the hardest. His conclusion is succinct and in keeping with the moderate stand he takes throughout. I will let the reader make their own judgement. A summary of the chapter appeared in Commonweal in November 2011.