Scarlett Johansson is the happiest she's ever been since falling for her The Black Dahlia co-star Josh Hartnett. Johansson, 21 and Hartnett, 28, began dating while shooting the 1940s murder mystery in Hungary, and she's convinced she's found her soul mate. She says, "If you're in a supportive and loving relationship, well, there's nothing like it! "It's a real blessing knowing there is somebody who is there for you, somebody with whom you can share the stories of your day, and who is sympathetic to what you're going through. "Josh and I have the same attitude to our careers. Josh is a great actor - even before I knew him as a person, I admired him as an actor. "He's serious about his work, dedicated and very focused."