Credit: Araya Diaz/Getty Images for Dreamworks Photo: Alex Pettyfer and Dianna Agron Attend the "I Am Number Four" Signing at Hot Topic on January 29, 2011

Looks like things between Dianna Agron (Quinn), 24, and Alex Pettyfer, 20, have hit overdrive. The adorable couple are reportedly engaged!

A source tells People, “They're very happy about it.”

Dianna showed up for a press junket for I Am Number Four wearing a thin diamond band on her left ring finger, but said that her love life is "something I never like speaking [about].” Still, she did offer that working with Alex on the film was “great [...] because he was so enthusiastic and so determined to give everything he had to this character. He wasn't a diva, so that was good."

Source: People