Once every four years, mortal rugby enemies become comrades in arms as the elite international players of England, Ireland, Scotland and Wales combine to create one team to take on the giants of the southern hemisphere. That team is the British & Irish Lions. It is on Lions tours - to New Zealand, South Africa and Australia - that lasting reputations are forged in the heat of battle. It is where good players become great players. But who are the greatest of the great? Who are the fifteen best players ever to have represented the Lions? Was Willie John McBride better than Martin Johnson? Was Barry John better than Jonny Wilkinson? Was anyone better than Gareth Edwards? As incisive and decisive as he was on the pitch, Jonathan Davies has the answer to all these questions and more.