This year’s Summer Sonic had its craziest moment on Sunday night when 1980s singer Rick Astley joined the Foo Fighters for the latter’s headlining performance.

“Come on you motherf———!” Astley bellowed at the thousands of fans gathered in Chiba’s Zozo Marine Stadium, with the U.S. rock outfit laughing hysterically. They then ripped into a mash-up of Nirvana’s “Smells Like Teen Spirit” with Astley’s hit-turned-meme “Never Gonna Give You Up.”

It was a fitting climax to a weekend that saw viral goofball Pikotaro open the main Marine Stage on Saturday morning with a frantic 15-minute-long performance, and over the course of two days — held concurrently in Tokyo and Osaka on Aug. 19 and 20 — featured AKB48-adjacent idols, sea-side screeching and a handful of political statements.

The two days out in Chiba for the Tokyo leg got weird, which may be a good look for the festival that caters to city folk. The past few years have seen the event, held since 2000, undergo a bit of an identity crisis. The 2015 edition leaned in on pop, eyeing younger fans while pushing away the festival’s long-standing rock demographic. Last year, they reversed course by placing the emphasis back on guitar-centered acts.

Yet this year, Summer Sonic struck just the right balance between dance-pop and rock, the two styles that work best live in Japan. Those not keen on throwing their hands in the air for Scottish DJ and producer Calvin Harris’ headlining set Saturday could mosey on over to the Mountain Stage to watch the band Kasabian. The next day, Swedish EDM duo Axwell & Ingrosso offered an alternative to the chugging sounds of Foo Fighters. Alongside a heavy focus on domestic rock acts, Summer Sonic figured out the best way to indulge both worlds.

Part of that involved the festival embracing its past. Summer Sonic was long celebrated for its punk and hardcore offerings, somewhat lost during its recent scramble to get with the kids. Sunday was the unofficial “rock day” of the weekend, managing to bring in around 45,000 people — 5,000 less than the day before.

You wouldn’t know there were less people at the Sonic Stage, though. It was crammed from noon till night, hosting long-running North American acts Sum 41 and Good Charlotte, along with Japanese outfits Blue Encount and Totalfat. In Totalfat’s case, even the security appeared absorbed in the performance, snapping photos when they thought nobody was looking.

Peak Japanese rock at Summer Sonic came in the early evening at the Marine Stage Sunday, when Japan’s own Man With A Mission took to the stadium. The quintet, best known for its members sporting wolf heads on their noggins during live shows, packed the venue and got the crowd moving by running through pop-punk, nu-metal and hard rock cuts that sent water bottles flying.

Man With A Mission also delivered Summer Sonic’s clunkiest political message. The group’s set opened with a video featuring footage the Israeli-Palestinian conflict before a segment implied that these five furry rockers could bring peace to the world. Embarrassing? You bet!

The politics didn’t stop there. American acts expressed sentiments both vague (pop act Kesha performing in front of the words “F—- The World”) and specific (rapper G-Eazy performing in front of the words “F—- Donald Trump”). Black Eyed Peas called on Korean performer CL to join them for the “All Lives Matter” of 2000s pop, “Where Is The Love?”

Cloying messages aside, the U.S. trio (“What happened to Fergie?” was a popular question on Twitter from Japanese users) delivered an up-tempo set worthy of Summer Sonic’s “pop day.” Other highlights included Swedish singer Zara Larsson packing the Mountain Stage and French band Phoenix stealing the day at the same spot a few hours later.

Domestic acts won again, though, with crowd size. Kyary Pamyu Pamyu and Yasutaka Nakata’s show at the Sonic Stage was going to be filled up thanks to the chance of British artist Charli XCX showing up for a guest appearance, but even after she cancelled her Summer Sonic set due to health concerns, the Japanese duo shined by mixing Kyary’s playroom pop with Nakata’s drop-heavy dance numbers, resulting in roughneck takes on now-entrenched J-pop hits such as “Fashion Monster.”

Summer Sonic’s renewed focus on rock and dance-pop worked wonders, but it did push other styles to the edges. Rap and R&B felt sparse, most of it pushed to the Beach Stage, attracting so-so crowds to the fest’s most sweat-drenched spot (which did make for the most mismatched image of the weekend, during singer-songwriter Seiko Oomori’s throat-tearing performance Saturday). The one exception came at the Space Odd Stage, a small spot promoting a new live venue, Space Odd in Daikanyama (the whole area the stage was in was basically themed after Daikanyama). It hosted Japanese rappers such as Chelmico and Akko Gorilla, who surprised with strong crowds.

The festival also made room for more unexpected bookings. The biggest curiosity came Saturday night, when dozens-strong idol unit Keyakizaka46 took to the Rainbow Stage. It’s one of AKB48’s officially sanctioned rivals, and has managed a fair amount of mainstream attention thanks to lyrics with a darker bent on teenage life — though the words are still penned by Yasushi Akimoto, a 59-year-old man, so don’t get too excited about progressive pop. It was packed for opening number “Silent Majority,” but soon thinned out as people got a glimpse of the idol outfit and decided that was enough.

Novelty — from uniformed idols to the Foo Fighters Rickrolling a baseball stadium — abounded, but the biggest act of the weekend showed how even a silly idea can evolve into something more. Babymetal was Sunday’s penultimate act at the Marine Stage, but easily brought more fans into Zozo Marine Stadium than any other act this year, including headliners Calvin Harris and Foo Fighters. Babymetal T-shirts were everywhere during the day, and watching the set from the upper deck of the stadium was like looking under a microscope and seeing cells learn how to make a mosh pit.

While there’s still a funny air to watching thousands of people run into each other during a song called “Gimme Chocolate!!,” Babymetal’s set worked as serious stadium-filling fare. The show opened with a slideshow of its history at Summer Sonic — including a 2012 performance in the food court — that showed just how far the group has come, adding an emotional hook to the show. From there, it was nonstop energy with the trio dancing and commanding the audience to lose it while their backing band shredded away. It wasn’t new, but everything was bigger and more exciting. Even those in the nosebleed section danced around, transfixed by the chaos below.

Babymetal combined all of the winning elements present at Summer Sonic 2017 into one package — it was rock-centric, anchored by pop hooks and fun. During a festival full of attention-grabbing moments, it was the peak, and it had the most to say on where Summer Sonic should go from here.

In line with COVID-19 guidelines, the government is strongly requesting that residents and visitors exercise caution if they choose to visit bars, restaurants, music venues and other public spaces.