The battle between 2006 singing idols Taylor Hicks and Katharine McPhee is reminiscent of a 1930s popularity feud between singing idols Nelson Eddy and Jeanette MacDonald. What’s different is that behind the scenes and unknown to their public, Eddy and MacDonald were longtime lovers.

As America awaits the voting verdict as to whether Taylor Hicks or Katharine McPhee is crowned this year’s American Idol, we are reminded of the singing idols of Hollywood’s golden years. But instead of battling it out on the television stage, Nelson Eddy and Jeanette MacDonald showcased their talents in a series of eight classic MGM musicals. For years, each film seemed better than the last: the sleeper Naughty Marietta (1935) was followed by the box office smash Rose Marie (1936) that was followed by Maytime (1937), the highest grossing film of that year. In 1938, they had yet another record-breaker with the studio’s very first colour film, Sweethearts.

While many fans adored them as a team, there existed a loud and large majority of moviegoers who preferred one or the other. Today, we cast our Idol votes by phone and text messaging. In the 1930s, votes were cast via fan letters written to the studio—thousands of letters a week. At their peak, Eddy and MacDonald received more fan mail than even Clark Gable! The Eddy fans wrote furiously to studio head Louis B. Mayer, complaining that Nelson didn’t make his first appearance in a team movie for 20 minutes, or that he had only x-number of minutes on screen and why was Jeanette allowed to hog the film? After all, Eddy was the better singer, they claimed! The MacDonald fans argued that Eddy couldn’t act and that MacDonald had to carry the film herself.

The fighting and bickering continued even after their MGM years. In 1945, when Eddy and MacDonald had left MGM and were considering producing their own films, one of Eddy’s fan club presidents went on live radio and denounced MacDonald as a co-star. Nelson Eddy was so furious he threatened to disband all his clubs. Fans puzzled by his reaction did not realize that on the sly, Eddy was in love with MacDonald. They had a tumultuous but intense love affair that had started soon after they met, and lasted until MacDonald’s death in 1965. Eddy died in 1967.

Today’s American Idol has a future of endless opportunities, the chance to create a career in the musical genre of choice. By contract, Eddy and MacDonald were imprisoned by their fame, not allowed to marry without studio permission (which was refused). Their lives took a sad turn and many fans mourned their disappearance from the silver screen. In a 1947 letter to Eddy, MacDonald wrote: “You said true love never dies…it becomes a miracle that can conquer death and live again in continual rebirth. Yes! My darling, it is ever true and I know it well—we are heirs to the grace of God….Your love awakened my sleeping soul and now life will forever be deathless and exalted.”

The poignant love story of America’s singing idols Nelson Eddy and Jeanette MacDonald is told in the biography Sweethearts: The Timeless Love Affair On-screen and Off Between Jeanette MacDonald and Nelson Eddy by Sharon Rich.