"Anybody run the marathon?" American Reunion star Alyson Hannigan asked as she sat down to talk with reporters about the fourth feature film in the American Pie series. It was the same day as the Los Angeles Marathon and she, along with co-star Jason Biggs, admitted to being "punchy," but ready to talk about the first on-screen appearance of a longtime cast member: Biggs' penis.

"She brings it out in guys," the actor joked. Hannigan's How I Met You Mother co-star Jason Segel also gamely drops trou in films.

"I think with this Jason, it was about time," she said with a laugh. "We've spent three movies talking about it. The pie got to see it. It was about time we got to see it."

"The penis has been a major player in the American Pie franchise," Biggs added.

"The Rosebud," she interjected.

Biggs said the reveal emerged from conversations with writers/directors Jon Hurwitz and Hayden Schlossberg. The actor wanted a scene as memorable as his infamous date with the pie in the 1999 original. "Some earlier drafts, it felt like it was missing,” he said. “I gave them carte blanche.” The directors were free to take Biggs' Jim Levenstein anywhere as long as it "makes sense in the context of the film and for the character." Also, it had to be funny.

Hannigan recalled that the nude scene was her first day of shooting. "It was quite technically difficult because I sort of had to become his eyes. He couldn't lean down and see, because then he wasn't squooshing it enough," she explained. Part of the day was spent deciding which position -- "The Two O'clock," "The Sydney Harbor Bridge," "The Straight-Up Hot Dog Bun" and the "Dead Insect on the Windshield" -- was funniest.

"The options were endless," Biggs said.

An earlier version of the script featured a domination scene between the two, and an echo of it remains in the final film, something the actor used an example of the challenge of pushing boundaries.

"Now that you have these characters in their 30s,” he said, “it's tougher to find situations where you can put them in these ridiculous scenarios that are believable." At this stage in their lives, he pointed out, the antics could become illegal. "Some of the things they did in the previous movies would not be acceptable for a 30-year-old. So they had to update it. I think that's why the penis scene works organically -- 'organ' being the appropriate root word."

For Jim, the situation is all too familiar, much like the sexual frustration he encounters in the film. "I love that [about] Jim," Biggs said. "Despite that he's grown up and married, he finds himself in a situation where he is once again sexually frustrated. When Jim is frustrated, he ends up making some poor decisions. When he makes some poor decisions ..."

"We make a movie," Hannigan interjected.

After a laugh, Biggs continued, "The truth is, after 30, men still masturbate. There are still sexual problems that happen, that arise for guys."

"Jason, do you want to tell us something?" Hannigan asked.

"I'm masturbating right now," Biggs replied. "As we speak. Under the table."

After the laughter died down, the actor was asked about Kara, the girl Jim used to babysit, played by Ali Corbin, and if men over 30 are just naturally attracted to young girls.

"I think the fact that he used to babysit her ... or that she just turned 18 and [she's] in high school and the just-legal aspect," Biggs stammered. "I don't know. I'm married. I'm not attracted to any other woman, ever. I heard she showed her boobs in this movie, is that true? Did that happen?"

Hannigan added, "I think it's more that this beautiful, [young] woman is aggressively coming on to him."

Because the actors have grown up more or less alongside the film series, they found they could relate to their characters' primary dilemma. "My situation was not as extreme as Jim and Michele's, of course, but when my daughter was first born, we were all-consumed with just her," Hannigan said. "It was probably quite a few months before we realized, ‘Wait, we do need to set aside a date night instead of trying to fit it in between diaper changes.’" Even if that date night turns out just to be "a dinner not interrupted by a 3-year-old," she said it’s still an important aspect of her relationship with her husband.

"For me, the biggest change in my life, personally, has been getting married," Biggs added.

For him, becoming a husband shifted his focus away from things he now considers "selfish." With his priorities realigned, Biggs said he realizes the next step is kids. "That'll be a game changer," he said. "It's interesting to see Jim wrestle with those same sort of big ideas. It's not just about him anymore. You think about the first movie, the whole movie rests upon these guys wanting to get laid. It's very me me me."

The actor also relates to the changing relationship between Jim and his father, played by Eugene Levy. "I've found as I've gotten older, too, that my dynamic with my parents has changed quite a bit," he explained. "When Jim offers his dad advice in this movie, it's kind of flipped. I think that's really cool." He credits Hurwitz and Schlossberg with not only maintaining the character interactions, but finding new takes on it.

In discovering those new angles, there was one storyline Hannigan found mysterious and enjoyable. "I love the MILF Guys storyline," she said. "I love that we don't know why they broke up."

"We're not saying that they're gay, just that they're buddies," Biggs explained. "We've never intended that, but people have been questioning." He suggested John Cho's performance as MILF Guy #2 might be leading people in that direction, but that the real question is just what tore the MILF Guys apart.

"Maybe a MILF came between them," he added, aware of the pun.

America Reunion opens April 6.