Transcript for Joe Manganiello dishes on 'Smurfs: The Lost Village' live on 'GMA'
see. I have a 2 1/2-year-old niece and 2-year-old nephew and aren't going to be allowed to watch anything uncle Joe has done for a very long time and I have to serve on the board of trustees for Pittsburgh children's hospital and although it's not at all why I do it but I go to the hospital and visit the kids and for years they would say who are you? That's a good thing. Now they know. They go to the hospital. I have to say, it is a little hard to imagine you as a smurf so we'll give everybody a look. Don't let them escape. Is this safe? Well, it's a giant crossbow so I'm going to go with no. Aaagh! Ooh. Incoming bird. Oh. I love those movies. I took my twins to see this a few weeks ago and I'm like still sitting there like that you play hefty smurf. I play hefty, yeah. Strong smurf. Strong. So when you saw the script what made you say yes to doing this. Hefty is such a fun character because he's this big but he's like Normal size strength in a tiny little body and then the other side of it it's juxtaposed with this -- he's kind of this clause sought poet. He's in love with smurfette and sometimes it comes out in very embarrassing moments so a fun thing to play with a little character. How did you like doing an aimed movie versus doing the regular kind. You get the roll into work with your sweat pants on, baseball hat like it's the best job. Roll in by yourself. Knock it all out. You never work with anybody else. Just straight to the screen. I never worked with anybody else. You know, it was funny. This week, this week, demi and Mandy patinkin and went to the united nations to speak at the united nations with our giant smurfs, yeah. For smurf rights. No, it's international happiness day today. We were there to award exemplary kids who had done extraordinary things in order to help the world to become more sustainable so giving awards away to these kids but we were there and I never met Mandy but we were in this movie together which is kind of interesting. You're also doing a project with Dwayne "The rock" Johnson who is also just an incredible guy. Can you tell us about that. "Rampage." Based on the 1980s video game about giant monsters smashing cities. Should be pretty fun. Niece and nephew won't watch that for awhile in maybe a couple of years but "Magic Mike" maybe never see that ever. Ever. That's kind of an ever movie. Ever. What was he like on the set? He didn't show up with clothes on. Brave. I want to say that I think -- maybe there was maybe like 90% of that scene that the general public did not see because we were -- there is somewhere. But you just said that. S there he are some lost tapes of this guy doing amazing things. Love karaoke. Yes. Which Amy and I love to hear, he hear. What is your go-to song. I've got a surprising strong falsetto voice. Whoa. Didn't see that coming. Something you don't know about me. So probably prince's kiss. There was this famous "Magic Mike" one. We went to this bar in Tampa, Florida. DI prince's kiss and followed up with bon jovi. "Smurfs: The lost village" hits theaters March. For all those pokers,
This transcript has been automatically generated and may not be 100% accurate.