New Series 1/3. When John Met John. On Thanksgiving night, 1974. on the stage of New York's Madison Square Garden, Elton John , then the bestselling artist in America, announced a surprise guest to the delight of the ecstatic crowd. Another titan of rock, John Lennon , walked on stage and sang with Elton in what was to be Lennon last. public appearance before his assassination. Paul Gambaccim was there and shares his memories of the unique event with musicians and audience members who were present when history was being made. producer Marya Burgess