Book 16

Pyramid Plot

by Justin Somper and Somper

Published 31 August 1991
Action-packed stories of mystery and adventure interwoven with puzzles to solve

Book 17

The Invisible Spy

by Mark Fowler

Published 30 November 1993
Action-packed stories of mystery and adventure interwoven with puzzles to solve

Book 18

The Emerald Conspiracy

by Mark Fowler

Published 30 September 1993
Action-packed stories of mystery and adventure interwoven with puzzles to solve

Book 25

Crimebusters Investigate

by Mark Fowler

Published 27 October 1995
This is the latest title in the popular Usbo rne Puzzle Adventure series in which each action-packed stor y combines a good read with challenging and fun puzzles. Whe n the Orlando jewels are stolen, the Crimebusters are called in to investigate. '

16-18