Trevor is a British boy Numbuh 1 met on the flight to England in Operation: E.N.G.L.A.N.D. The one thing they have in common is that they were both born in England, but moved to America (Numbuh 1 at age three, Trevor a couple of weeks prior to the episode). Trevor enlists Numbuh 1's help in returning a book to the Great Library before midnight. Their tactics were delayed when they ran into the KND Sector E agents and the Rowdy Hooligans From Across The Square, who both wanted to get their hands on the book. The book turned out to be a Rainbow Monkey book instead of the Book of KND. Unfortunately, the Great Library closed and sadly, Trevor had to pay the overdue fine of 25 pence.