Illustrious pianist Leon Fleisher collaborates with his wife and fellow pianist Katherine Jacobson on his latest release, "Four Hands." The album features duets for four hands on a single keyboard, including Brahms's famous "Lieberslieder-Walzer," described by Ernest Lubin as being "among the loveliest and most beguiling of all Brahms's compositions." Discover its charm and more on Monday's program.