The third Usborne book of puzzle adventures : three adventure stories with puzzles to solve.
Somper, Justin.Pyramid plot.
Fowler, Mark.Emerald conspiracy.
Fowler, Mark.Invisible spy.
London : Usborne,
1993.
Cover title.
Spine title: Puzzle adventures III.
The pyramid plot / Justin Somper -- The emerald conspiracy / Mark Fowler -- The invisible spy / Mark Fowler.