If you want to understand anything about hat Christians believe, you cannot ignore the cross. Wherever you go in the world, wherever there are Christians, you will always find the cross because 2000 years ago the very first Christians said that Jesus had died in Jerusalem on a cross. They said he had been crucified as the 'Lamb of God' and that he had risen again 'from the dead'. But how can we know if what they said is true? And why did they call Jesus the 'Lamb of God'; what does that mean? Presenter, Luke Waldock, travels to Jerusalem to see the places where Jesus himself would have walked during the last few hours of his life. He sifts through the evidence- historical, medical and theological- and he finds answers.