This picture was taken in April 1964 during rehearsals for the Ready, Steady, Go Mad Mod Ball at the Empire Pool Wembley (later the Wembley Arena, now the SSE Wembley Arena).
Apart from the Beatles, who that week held the top five records in the US, just about everyone of note from the Merseybeat boom is here.
Of the 40 faces here how many can you identify? Some are obvious but others are perhaps not so easy.
I’ll post a key diagram and a list of names shortly.