TARANTINO RECENTLY suggested Scorsese's best days are behind him. Kundun, Bringing Out The Dead, Gangs Of New York—it's not just that these movies struggled to connect with audiences, Scorsese himself seemed unable to get a firm grasp on them. Is this still 'the greatest living American film-maker'? At least this long-overdue three-film box set reminds us how he earned that title. Check out his 1969 debut, Who's That Knocking At My Door?