Marc Anthony's 'In the Heights' drama even shocked star Anthony Ramos: He was 'coming for blood'

For the wondering multitudes who saw "In the Heights" over the musical's opening weekend – yes, that was Marc Anthony in that stark mid-movie scene.

Anthony, the global music star ex of Jennifer Lopez, is nearly unrecognizable, looking worn, unshaven and unkempt while swilling beer in the morning.

His character was created for the film, the alcoholic uncle to Usnavi (Anthony Ramos) and father of young Sonny (Gregory Diaz IV). In the scene, Usnavi discusses Sonny's future, but his father is more attentive to the baseball game on the TV.

It's gritty.

Ramos says he kicked up his drama game when he saw how in-the-zone Anthony was.

"Yo, I was bugging," Ramos says. "I was like, 'Hey, I better bring it, because my man is coming for blood.' "

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"That scene is going to surprise audiences. People are not going to expect Marc Anthony to do something like this, so it's really special," says producer Scott Sanders.

Anthony, born in New York City to Puerto Rican parents, was a major fan of "In The Heights" during its 2008 Broadway run and saw it multiple times. So when the father role was written, producer Lin-Manuel Miranda texted Anthony, who has appeared in films such as "Man on Fire" and "Bringing Out the Dead." Anthony immediately signed on.

When the superstar singer first visited the Washington Heights set to discuss the role, he was followed by so many fans and paparazzi that director Jon M. Chu had to take shelter and hold the meeting in Anthony's besieged limo-van.

"People were banging on the windows, there was security, it was no joke," says Chu, who wanted to make sure Anthony was ready for a small but gritty role. "Marc was like, 'I'm coming, not as the Marc Anthony you know, I'm coming in.' "

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But Chu wasn't sure what Anthony was really going to bring, especially when the star showed up to the squalid apartment set wearing his trademark star sunglasses and attire.

"I was wondering if he was going to be present enough for these important scenes. It was like, this could ruin it," Chu says. But Anthony took off the glasses and said to his worried director: "I got this. Don't worry. Just watch."

To Chu's surprise, Anthony became the character once he donned the attire and settled on the couch.

"The guy brought it," Chu says. "Two seconds in and I don't really know if he was drunk or what's going on. He's out of it. And then right after he's just Marc Anthony again. He was like, 'Was that OK, Jon?' I was like, that was amazing. Do more."

It was Anthony's idea to make unsteady hand movements and to slovenly have his belt unbuckled. Why those choices?

"Honestly, I don't even quite understand just what he's saying (with that disheveled costuming). He just felt it was very important to not have his buckle on. I'm not going to get in the way of it," Chu says.

Chu says there was far more of Anthony and Ramos shot that was even more powerful. But he had to cut the scene since it revealed a plot point he wanted to keep under wraps.

"Hopefully we get to release that at some point since it's even better than what you saw," Chu says. "That guy will win an Oscar one day if he does more movies. For sure."

Dramatic actor Jimmy Smits, who surprisingly sings and dances for "In the Heights," was inspired by world music star Anthony's nonmusical cameo appearance.

"The dramatic guy sings here, while the major singer does this dramatic scene," Smits says. "But I've watched Marc's scene a few times, and I'm just sitting there going, 'Wow!' I just love the fact that he chose to do that. That scene was a gift to all of us."

This article originally appeared on USA TODAY: Marc Anthony's 'In the Heights' drama role: He 'was coming for blood'