ronald reagan ( he john ) love patricia neal ( she mary ) and but he marry to his best friend girl . there be a very good reason represent best friend jack carson save mr. reagan life during world war ii and reagan married lily to help his buddy out you see and lily need an american husband to obtain passage to the usa . meanwhile and mr. carson have marry another woman even for the time and the comedy dialog in john love mary must have sound remarkably unsophisticated while listen and for example and to the scene when reagan explain how he deal with loneliness during his four year of service . the performance match the low average nature of the proceeding . most notable a patricia neal ( inauspicious ) movie debut . john love mary ( 2/4/49 ) david butler ~ ronald reagan and patricia neal and jack carson .