Pictured above: Jimmy Stewart and Jeanette MacDonald in Rose Marie (1936), a scant two years before Stewart became a bankable leading man with Frank Capra's You Can't Take it With You.
Next up is Conquest (1937) with Greta Garbo and Charles Boyer, directed by the under-appreciated Clarence Brown, a director who never directed a movie that would appear on anyone's "Greatest of all time" lists but nevertheless produced one solid entertainment after another for most of his career.
Third in line we have La Boheme with Lillian Gish and John Gilbert, a silent from 1926. La Boheme the silent feature obviously has none of the music of the opera, just the story which was adapted from the work of Henry Murger, La Vie de Bohème. It also contains an early performance by the great character actor Edward Horton, in only his fourteenth role. Yes, fourteen sounds like a lot but it's early in your career when you end up making 175 movies!
Finally the great Frank Borzage directs Maureen Sullavan and Robert Taylor in Three Comrades from 1938. This is a Borzage I haven't yet seen but look at this cast: Maureen Sullavan, Robert Taylor, Franchot Tone, Guy Kibbee, Robert Young, Lionel Atwill, Monty Woolley, Henry Hull and even Charley Grapewin a year before playing Uncle Henry in The Wizard of Oz. Taylor was never a favorite of mine but I've always been fond of Tone (a great wisecracker for the uninitiated), Kibbee and Lionel Atwill, recently profiled on TCM's Movie Morlocks here.