Bing Crosby musical double-bill. In ' Rhythm on the River' (1940), Basil Rathbone plays celebrated composer Oliver Courtnay, but what his adoring public don't know is that his hit songs are composed by two ghost writers, Bob Summers (Crosby) & Cherry Lane (Mary Martin). When the duo decdie to strike out on their own, they find the going tougher than they thought, & are forced to fall back on Oliver for help. ' Rhythm on the Range' (1936) is a musical western, where Crosby plays a championship rodeo rider heading back west after making his name in New York. On the way he stumbles across runaway heiress Doris (Frances Farmer), who is looking for romance with a real-life cowboy.