Sean Connery wears a very Bond-like midnight blue dinner suit in Marnie. The jacket has straight shoulders on the natural shoulder line with roping and less dress drape in the chest than the other tailoring in the film. It has a button-one front and a midnight blue satin shawl collar. The jacket also has 3-button cuffs, jetted pockets and no vents. The buttons are probably horn, but may also be plastic, which was very common on dinner jackets in the 1960s. The trousers have double forward pleats and side adjusters.
Like in his Bond films, Connery wears neither a waistcoat nor a cummerbund in Marnie. The bow tie is midnight blue satin silk in a batwing shape. He wears a regular white shirt, with a spread collar and button cuffs. It has a placket with stitching closely spaced down the middle and mother of pearl buttons. A regular shirt can work for black tie in a pinch if it has double cuffs and no pocket, but the button cuffs on this shirt make it a less than ideal choice for black tie. The closest to a regular shirt Bond wears with black tie are the white-on-white stripe shirt in Thunderball and the voile shirt in Octopussy.