During a rebel attack on the Gosport Navy Yard, U.S. Navy Lieutenant Kenneth Reynolds defies an order to burn his ship, the Merrimac, which is then set ablaze by the retreating Federals. In an effort to save the vessel, Reynolds sinks her. The scuttled Merrimac is subsequently raised by the Southern Navy and rebuilt into a powerful armor-clad warship. Dishonorably discharged, Kenneth watches the war from the sidelines until he is reinstated to the Monitor, the Federal ironclad designed by his uncle, John Ericsson, to challenge the resurrected Merrimac. Lives are at stake, as is the relationship between Kenneth and his fiance, Constance, when they learn that her brother Raymond is an officer aboard the Southern warship. The looming confrontation between the two armored vessels will change the nature of naval warfare for all time.Hearts In Bondage was the only dramatic film directed by actor Lew Ayres, who rocketed to fame six years earlier, following his starring role in 1930's Best Picture winner, All Quiet on the Western Front. Leading man James Dunn, who had earlier appeared in Shirley Temple's first three features, would later collect a Best Supporting Actor award for his work in A Tree Grows in Brooklyn (1945). David Manners was discovered by director James Whale in 1930 and went on to appear in Universal's horror classics, Dracula (1931) and The Mummy (1932). Charlotte Henry starred in Alice in Wonderland (1933) and appeared in Laurel and Hardy's March of the Wooden Soldiers (1934). Mae Clark was featured in James Whale's masterpiece, Frankenstein, in 1931, the same year that she took a grapefruit in the kisser from James Cagney in The Public Enemy.