Malcolm: Malcolm is the main character of the story. In the beginning of his school life he was the smallest boy among his friends hereby his nickname is Mouse. Mouse is not a very sportive guy, rather a little bit lazy. He is a shy person and sometimes he's scary. On the trip he breaks his ankle.

Scott: Scott is the oldest boy from the group of friends. He's very cantankerous because his parents are divorced and his father left the house. He behaves like a leader, but he isn't the leader. Despite everything he's a very lovely boy by nature.

Dario: Dario is a friend of Mouse and also goes on the trip. In the rest of the book there isn't much to tell about Dario.

Ryan: There isn't much to tell about Ryan. 

Linda: Linda is the mother of Petra. During the trip Linda got hurt in The Straight Shooter.  She braught her cellphone, if she didn't bring her cellphone maybe she and the others would have died.

Petra: Petra is the daughter of Linda. Linda and Petra went on the trip for a mother-daughter time.

Rick: Rick is the owner of the White Water rafting company. He is also an instructor for the trip. The business he's running wasn't going very well. They thought the company would be bankrupt if this trip went wrong. Unfortunately it did.

Hall: Hall is the son of Rick and also a instructor on the trip. He thinks he's a very good guide, but Scott has other feelings about that opinion.