Session 1, "The Challenge of Faith," looks at the difficulties of having faith and what non-Christians think faith is.
Session 2, "Dealing with Doubt," focuses on the coexistence of faith and doubt.
Session 3, "Evil and Suffering, Part 1," gets into the difficult question of how God can be good but still allow bad things to happen.
Session 4, "Evil and Suffering, Part 2," asks what purpose there is in evil and suffering and if it can be used for good.