Puzzles containing hidden scrolls sound like the kind of things you would expect to find in Indiana Jones' study or that guy out of the Da Vinci Code's cupboard. But there are several sitting right here at Firebox as we speak. Unless of course they are out of stock, in which case you can see how hard to get hold of/popular The Equation really is!

The what? The Equation, of course. This maddening wooden puzzle is the successor to Da Vinci's Secret and it's even more vexing than its predecessor. Gorgeously crafted, The Equation is second in the Sacred Myths and Legends series of puzzles, a sequence of mind-manglers that must be solved sequentially. Why? Because each puzzle contains clues, hints and codes to help solve subsequent puzzles.

In a nutshell The Equation consists of a wooden frame within which you must arrange various wooden pieces of different shapes and sizes. Once you have solved the puzzle you'll discover a hidden scroll containing clues to the next puzzle in the series. And if you think that sounds easy, think again. The Equation's design has been influenced by the work of Galileo, Newton and Einstein. Piece of cake, then. Not.

We've been fiddling with The Equation for some time now (okay, every waking hour) and we're still utterly flummoxed. Indeed the hammer and chisel-method is becoming an increasingly attractive option.

If you're one of the smug puzzlers who managed to crack Da Vinci's Secret you should have already hit the Buy button. But if you haven't, listen up: after a single fiddle with The Equation we guarantee you'll become completely obsessed with releasing the scroll. In fact speaking of equations: this puzzle+you=aargh!