Mark Ruffalo knew the jig was up when he went to a Chuck E. Cheese pizza parlor the other day.
The actor, who stars with Reese Witherspoon in the romantic comedy "Just Like Heaven," was celebrating his niece's birthday when they began to cluster. And stare en masse.
"It was a bunch of young girls," says Ruffalo, 37, the married father of son Keen, 4, and daughter Bella, born in May. "They were standing in close proximity. I said, 'Hi. How are you?' One of them asked (he puts on a high girly voice), 'Are you Matt from "13 Going on 30"?' They were nice and everything. But I usually like to be low-key and private."
It's one thing to have female strangers 21 and over gaze at you in public with lust in their hearts. But it's another when pubescents profess love for Ruffalo, who played the hot adult version of the sweet junior-high chubster who stands by Jennifer Garner's suddenly grown-up magazine editor in the 2004 fantasy. "It's so pure," he says of the increasing incidents of spontaneous idol worship. "But it makes me uncomfortable."
Up until now his fan collective has been content to be respectfully enraptured. "What you get in the forums is, 'I watched this movie and I can't stop thinking about him,' " says Elizabeth Covington, 22, of Ann Arbor, Mich., who began the shrine markruffalo.net last year after she saw four Ruffalo films in a row. She considers him "the married woman's guilty pleasure."
There's no guilt, just pleasure for forum regular Donna McCulloch, 48, of Round Rock, Texas. "He's the only person I go ga-ga over except my husband. There is a genuine quality to him."
The staring, however, is likely to cross into full-blown gawking now that "Just Like Heaven," which is basically "Ghost" with a few more jokes and a medical condition, is in theaters. Ruffalo plays an adorably antisocial architect whose apartment is haunted by the feisty spirit of Witherspoon, the previous tenant who is in a coma.
And if that's not enough, Ruffalo plays Jennifer Aniston's staid fiance who is caught up in her sudden realization that her family may have inspired the events in "The Graduate" in "Rumor Has It," a hotly anticipated romantic comedy opening in December.
When did Ruffalo, the poster boy of independent cinema who was mentored by the mistress of Method acting herself, Stella Adler, and who has been declared "the next Brando" ever since his breakout as Laura Linney's well-meaning mooch of a brother in 2000's "You Can Count on Me," suddenly become the go-to guy of chick flicks?
"I wouldn't have done 'Just Like Heaven' three or four years ago," he says. "But then I thought, 'Maybe I'm more of a man for doing a romantic comedy.' "
After a health scare in 2002 when a benign brain tumor left his face temporarily paralyzed, Ruffalo has become bolder in his choices. "All I have to do is be true to myself," he says. "God hasn't carried me this far just to drop me."
For a passionate, often intense performer like Ruffalo, doing something lighthearted is a challenge. Convincing Hollywood he can is even a greater challenge.
"I was hearing from the powers that be that Mark Ruffalo can't do romantic comedy," says the actor, who has also dabbled in the action genre with less success in "The Last Castle" and "Windtalkers." "Those are fighting words to me. My wife thinks I'm a romantic lead. Why not do it?"
After "13 Going on 30" caught on, "studios knew he wouldn't do a commercial film and tank it or make it too 'indie,' " says Mark Waters, the director of "Just Like Heaven" who also did "Mean Girls" and "Freaky Friday." "Who else is out there who can be funny, serious, romantic but not a pretty-boy model?"
As Hollywood Reporter deputy film editor Anne Thompson observes, Ruffalo's most valuable commodity for now is talent, not star power. "They're not banking on him necessarily to open a movie. They are banking on him to make the leading lady sexy and make her look good."
He's one Prince Charming who can hold his own opposite A-list screen queens. Says Waters: "Reese was concerned about who got the part. She was psyched about Mark because she knew he would raise the bar."
A friend of Ruffalo's since the days when the actor was in small theater productions in L.A., Waters also trusted him to pull off "Heaven's" occasionally broad humor. "This is really the story of David," he says of Ruffalo's character. "One of the reasons he is great in the part is that he helps twist the expectations of what is a Reese Witherspoon romantic comedy. This isn't schmaltzy Tiger Beat acting."