-Welcome back to "The Tonight Show." We're about to play a game called "Box of Lies." But I'm gonna need some help. She stars in "Stranger Things." Season 4 premieres May 27th on Netflix. Please welcome Millie Bobby Brown! [ Cheers and applause ] Come on, now. Come on! Are you kidding me? Come on. It's so good to see you. I miss you. -Good to see you, too! -Millie, here's how it works. We have nine mystery boxes containing objects no one has ever seen before. Okay? On your turn, you pick a box, take out the object, and describe it to your opponent. -Can I sit down? -Yes, please. -Oh, my, I'm -- You're not even ready for this. -No. Really? -No. -You have to describe what's in the box, put it out there, and then I and you decide if we're telling the truth. I can't even look at you. Or if we're lying. Okay? -Alright. -Are you already playing right now? I'm in your head right now. -I don't even know if you know what I'm thinking right now. -Yeah, I totally do. You have no clue. Are you ready to go first? -Oh, my God. -That's the way I talk. That's the way I talk to you. -That was berating me. -It was, right? All right, bud, you're up first. You can pick the first box. -Alright. -Which one? -Four! -Four. -He was so passionate about four. -Yeah, he was very passionate about four. -Alright. [ Audience shouting ] -This could be a hint right here. -Oh, my gosh! -Yeah. It looked like it was a little light. -No, I've just got huge guns. [ Laughter ] Huge guns. -Huge guns. Alright, bud. -Okay. -Yep. [ Clears throat ] -[ Chuckles ] [ Laughter ] -Okay. -Alright. [ Dramatic music plays ] -The music. Alright. Jimmy. -Mm-hmm. -Um, this almost looks like a children's play set kind of. You know? Something that a child would play with. And it's the Demogorgon from the show, a toy Demogorgon, painting E.T. -A children's play set. -Yep. Yep. -What does that mean again? -I don't know. It's up for interpretation. -Children's play set. -And It's painting E.T. with my eyeshadow palette from Florence by Mills. -Ah! Now, I know -- I love Florence. -Yes. -I know your makeup line, yes. -And, um, that's what he's doing. With a makeup brush. -E.T. Yep. Uh-huh. E.T.. And you've seen the movie "E.T." -Um, I don't know. Have I? -You're very young. -Am I? [ Laughter ] -No, I actually know how old you are. Yes, you are young. But you've seen "E.T." before. You loved it? -Loved it. -Yeah. What character did you love in "E.T."? -E.T. himself. -Yeah, I know, but there's other characters in there. How about the boy? -I loved the boy. -Yeah. What was his name? -Elliott. -Hmm. You do know "E.T." -Or do I? Did I just read a synopsis before I came out here? -So you have a child's play set, is what threw me. That makes no sense to me, 'cause a child's play set -- -Well, do you have children, Jimmy? -Yes. They don't have play sets. -They don't have toys? -They don't have toys. -They're not real. -Toys are banned from the house. Toys are banned from the house. Only books. A child play set to me seems like a swing set or something. That's a play set. -No. I mean like a toy almost. You know, something that you go, "Oy, oy!" You know? -Yeah, a toy and a painting of a Demogorgon, E.T. Too many details. I'm going to say, Millie Bobby Brown, you lie! -Owwww. -Oh, my gosh! Are you kidding me? [ Sad tuba plays ] Come on. You're good. You know how to act. Come on. What am I talking about? Why mess with the best? Why mess with the best? I'm sorry. Of course you're going to be a good actor. Which one, guys? [ Audience shouting ] -I'm going to put -- My "E.T." for later. I'm going to put it this way. -[ Grunts ] -I'm here with you. -Okay. Alright. Here we go. Phew. Mm-hmm. ♪♪ [ Laughter ] ♪♪ [ Laughs ] -Uh-huh. -Oh, my goodness. -[ Mocking laughter ] Go! Tell me! -It is -- It's, like, a child's play set. [ Laughter ] ♪♪ It is a bowl. Full of Chef Boyardee. -What's that? [ Laughter ] -I don't know how to describe it. Pasta. -Okay. -Yeah, it's a bowl of Chef -- I should have said that. But it's Chef Boyardee, 'cause the can is next to it. It's a canned food in America. -Oh, okay. I'm from England. -Sorry. You're from England. Yes. -Yeah. -Yes, and in that bowl is a head that looks to me like Elon Musk. [ Laughter ] Elon Musk head in the Chef Boyardee. So it's like pasta with Elon Musk's head. -Okay. -Heads. -Heads? -Yes. It's, like, floating. -Multiple different heads? -Floating like -- -How many? -Four. -Four. I know you are lying. -How? -'Cause you're a horrible liar. [ Laughter ] -What are you talking about? Are you sure? -I'm positive. I don't want to ask any more questions. I know that you're lying. -No, no, no, ask me -- -No, I -- Okay, fine. Fine, fine! I'll ask you one more question. What shape pasta is it, Jimmy? -I was lying! You won! You knew! [ Cheers and applause ] It's spaghetti and meatballs. Baseballs. I thought maybe you could smell the pasta, so then I started trying to make something up. And I messed up. -You got nervous. You got really nervous. -I did, right? -As soon -- You know what -- Just for future reference. It's when -- I just want to make you -- As soon as I asked how many heads, you just went straight for four. -Oh. -When you just should have taken one more look at how many Elon Musk heads were in that bowl. -Yeah, yeah, exactly. I could really count four. -Well, anyways. -But I knew four. -It's my turn now. -Yes, it's your turn. Yes. [ Audience shouting ] Someone's saying eight. Five is the one. Okay. [ Thud ] -Did that scare you? -Yeah, it did a little bit. It woke me up. Okay, here we go. -Alright! -Okay, 'cause the first one was not a lie. So I figure, well, maybe this one you're gonna probably think of something. Or the pressure's on. Your face is getting red. So you're probably thinking -- -It's just my blush. [ Giggles ] ♪♪ Okay. -Mm-hmm. -It is... -Uh-huh. -...a Croc, sandal kind of shoe. -I know what a Croc is. -I don't know. You didn't know what a children's play set was, so... -Yeah, I'm sorry. Thank you. -Stuffed with pasta. Spaghetti pasta. Cooked. And it's going through the holes of the Croc. -Mm-hmm. Huh. -And there's a watermelon-flavored Sour Patch Kid in -- drowning, really, in the spaghetti. -Now, how would you know it's watermelon-flavored? -Because they're green on the bottom. And they're one of my favorites, actually. I eat them on set quite -- -How do you see the bottom if he's drowning in the -- -No, I see it. I can see it from the top. From the top angle, I see it's green. -Okay. -And also spaghetti is quite, you know, thin, so I can see through the spaghetti. -Oh, I know spaghetti, 'cause I was just lying about it. -I know. I know. -Yeah. So you're saying two spaghettis? That's -- What are the odds of choosing two spaghettis? -I don't know. Ask your writers. [ Laughter ] [ Applause ] -Oh, you're good. Oh, you're good. [ Applause ] Oh, you're good. ♪♪ I'm gonna say... you're telling the truth! ♪♪ [ Sad tuba plays ] [ Cheers and applause ] Oh, my gosh! You're so good! You're so good! Wait. Can I try? One more? -One more. -Yeah, here we go. [ Audience shouting ] -Three, Jimmy! -That's my man three right there. Yeah, look. So light. Oh, my gosh. It's like there's nothing in it. -[ Laughs ] -But there might be. Who knows? -You're so red. -Oh, my goodness. It's just awesome. [ Laughter ] ♪♪ You ready to get into this world? -I don't know. Am I? -I mean my brain. -Oh, yeah. -Yeah. See what I saw? Do you want to see? Maybe I'll take my time a little bit on this one. -Alright. [ Laughs ] -Is my acting getting better? -No. -It's a, uh -- baseball hat. -Mm. -But one that holds the drinks. ♪♪ And one drink -- You know those people that have beers -- -No. I've never been to a baseball game. -Oh, my gosh. -Is it where they drink the beer through straws? -Yes! One -- Instead of beer, though, one is Pepto Bismol. And one is... [ Laughter ] One is... Hmm. What is that? [ Laughter ] I learn from the best, bud. One is, uh, hot sauce. -What kind? [ Laughter ] ♪♪ -I'm not wearing my glasses, of course, but I can tell by the bottle that it's Sriracha. -Oh. Sriracha mayo or just regular Sriracha? [ Laughter ] ♪♪ -Regular Sriracha. -Uh-huh. This is what I'm going to say. I'm gonna say it is a partial lie. I think you are telling the truth in some places, but I think that I've got you on this hat. I don't think it's this kind of hat. You've accepted my suggestion far too quickly. I don't believe that it's one of those beer hats. -Yeah. How could it be? -I don't know. You tell me! -That's the game. So you have to make the choice. -You lie! -You think I lie? Oh, I tell the truth. -No! -Yes! Redeemed myself! I redeemed myself! Millie Bobby Brown, everybody! [ Laughs ] I'm so happy. I redeemed myself. -You did so good! -I did. I learned. I learned from the best. We're talking to Millie after the break. Stick around.