Thirty-three years after his final departure, Ritchie Blackmore says he plans to step onto a Deep Purple stage again — for one song, one night, and perhaps one final glimpse of a guitar chemistry that helped invent hard rock.

Mark Knopfler turns 77 today, and his playing remains one of the hardest things in rock to imitate. Not because the notes are difficult — because almost none of what makes it sound like him is written down.