Elvis also had an affair with his "Viva Las Vegas" costar Ann-Margret. She wrote about their relationship in her 1994 memoir "Ann-Margret: My Story." In her book, Margret described her romance with the heartthrob as "very intense." "We both felt a current, an electricity that went straight through us," she wrote, according to the New York Times. "It would become a force we couldn't control."
The couple appeared very smitten with each other as they even discussed marriage. However, Ann-Margret didn't think they would make it down the aisle due to Elvis's "commitments," seemingly referencing his relationship with Priscilla. Just like she predicted, Elvis and Ann-Margret ended up breaking up in 1964 and he went on to marry the "Dallas" actor three years later.
Image Source: Getty / Sunset Boulevard