This is a bit more for seminary students and up. It's an excellent overview of penal substitutionary atonement. I really liked the focus on the atonement and resurrection at the end of the first section defining the biblical basis for our "Divine Substitute."
The remainder (and majority ) of the book looks at both biblical, and unbiblical, views and the theological developments of the atonement throughout church history. As is always the case, so much of current liberal theology attempts to sound new, and yet has all been said before (though, usually repackaged to fit the times). Our culture is so quick to put the love of God as His primary attribute, with all the other attributes subservient to His love. Of course, whenever that happens, the love of God is the very thing that ends up getting smaller and smaller. Without the Covenant of Redemption planned before time and the perfectly holy God of wrath and judgment stepping into our fallen world through the incarnation, life, death, and resurrection of the second person of the Trinity, the love of the Father, Son, and Spirit becomes significantly less.
Praise the God who is. Only a Divine Substitute can save. Only.