Monty's father died when he was two, leaving him to be raised only by his mother. As a zoologist, she had to go to Borneo for a year, leaving Monty with his Uncle Leo for a year, along with his cousin.
He started to see an evil version of himself running around, and found out that his Uncle Leo created an evil clone of himself that then created evil clones of Monty. He also discovered that his cousin Nan is actually his sister, who his mother had to give up when they were young.
Monty was mistaken for the clones and was hauled away. While he managed to escape, an evil Monty tricked Nan and Monty was hauled away to South America, along with the clones.
Monty is embarrassed about his looks, as well as his full name, Montgomery. He claims to hate adventure. He proves to be quick witted when he tricks his clones into fighting with each other.
Monty is described as skinny with red hair and a big nose.
- The cover art depicts his hair as being brown, despite it being red in the actual book.