The second book in the series by Douglas Adams dealing with Dirk Gently. It focuses mainly on Norse mythology, a woman who was just trying to visit her boyfriend, and an Act of God. Dirk wonders, which God? And what was he/she doing at Terminal 2 at Heathrow Airport?

It also suggests that the 9/10ths of the human mind supposedly unused has penguins in it. Between them, Douglas and Linus have a lot to answer for.