Los Angeles, Jan 12 : Ahead of the 20th anniversary of their film '13 Going on 30', Hollywood star Mark Ruffalo has nothing but incredible things to say about co-star Jennifer Garner. The actor explained what initially brought him to the project and why it was the "wonderful chemistry" he had with Garner, 51, that hooked him, reports etonline.com. "It was my first kind of studio film and, you know, I'd been doing pretty small indies up to that point and Gary Winnick, our director, said 'I want to -- I want to do a small indie but in a rom-com studio film,'" he said, adding that the Winnick told him he would be opposite the Alias actress. "It was Jen Garner, who is just magical, and we had just a wonderful chemistry together," the Avengers star said. The film released in April 2004 and became an instant classic, boosting Ruffalo and Garner's own careers astronomically. Garner went on to star in Elektra, Juno, and Ghosts of Girlfriends Past while Ruffalo took on roles in Collateral, Zodiac and Shutter Island. He credits '13 Going on 30' with helping him to reach the next stage in his career and being cast in "elevated roles." "I think people started to see me in a lot more different kinds of elevated roles than what I'd been playing up to that time," Ruffalo said. As for what he would consider his favorite scene from the movie, Ruffalo said it's the tender moment between his character and Garner's on a swing set outside of New York City that comes to mind. "Probably the Razzle scene on the, out on the swings in the park," Ruffalo said. "Yeah, beautiful, sweet scene." The iconic film was released in April 2004 and also starred Judy Greer and Andy Serkis. /IANS