Complex sentence: They are all under the leadership of their by-the-book, Machiavellian chief clerk Peter McLeish, who is clever and obsessed by work and doesn't appear to have a social life.
Split into simpler sentences: They are all under the leadership of their by-the-book, Machiavellian Chief Clerk Peter McLeish, who is clever and obsessed by work. Peter doesn't appear to have a social life.