The White Knight & Black Valentine Series (Book 3): Almost Invincible

A theme park turns into a death trap of sadistic supervillains...

White Knight is the most popular superhero in the country--which is bad news for David Del Toro, formerly White Knight, who retired from superheroics years ago and just wants some peace and quiet. When the White Knight ride at a superhero-inspired theme park has a grand reopening, Dave is more than happy to give his complimentary tickets to his daughter and her friends and spend the day at home. But then the park gets taken hostage by supervillains.

The man known as Bloodbath spent the last decade in a maximum-security prison and blames White Knight for putting him there. He's given an ultimatum: the hero comes to face him, or he'll kill every tourist in the park. Dave barely managed to beat Bloodbath while in his prime and doesn't like his chances now that he's old and busted. But unless he does something, every innocent person in the park is going to die... including his daughter.