The Dark Tower IV: Wizard & Glass - Stephen King

And, having narrowly escaped one world, they set out on a terrifying journey across the scarred urban wasteland to brave a new world where hidden dangers lie at every junction: a malevolent computer-run monorail hurtling towards self-destruction, Roland's relentlessly cunning old enemy, and the temptation of the wizard's diabolical glass ball, a powerful force in Roland's first love affair. A tale of long-ago love and adventure involving a beautiful and quixotic woman named Susan Delgado.  And the Tower is closer...

Book shows signs of wear.