Lois Lane may play his onscreen love, but actor Henry Cavill's heart belongs to fair-haired equestrian Ellen Whitaker, 24.

Cavill, who will play the titular superhero in Zack Snyder's new Superman: Man of Steel film, proposed to his girlfriend of just over a year during a trip to Los Angeles, reports UK's Daily Mail. As far as Whitaker knew, they were on vacation to celebrate Cavill's birthday. But the British actor had called her father just days before to ask permission to marry his daughter. Then he got on one knee and popped the question in a Hollywood hotel room.

Whitaker, a dedicated showjumper who is training for the 2012 British Olympic team, was completely surprised. "I couldn't believe it when he asked me to marry him," she wrote on her website. "I thought we were there to celebrate his birthday. It was such a surprise and I am so happy."

Cavil celebrates his 28th birthday today. Superman: Man of Steel, which is in pre-production, is set for release in December 2012. Diane Lane, Amy Adams, and Kevin Costner have also signed to join the cast. —KIMBERLY STEELE