Ever since H1-KEY debuted in 2022, the four-member K-pop group has experimented with different sounds, from their bombastic Athletic Girl single album debut to the energetic and rebellious “Let it Burn” on last year’s more mature LOVE or HATE mini-album—because H1-KEY is always looking for new ways to express themselves.

Now, H1-KEY members SEOI, RIINA, HWISEO, and YEL are back with their latest mini-album, Lovestruck, and their new single, “Summer Was You.” Throughout the song, its vibrant sound and nostalgic lyrics about youth and summer nights make it an instant standout among K-pop tracks this year. Additionally, the track’s use of bright guitars gives it an edge that pierces like sunlight, and its infectious chorus is enough to bring a smile to anyone’s face.

The music video for “Summer Was You” depicts the members of H1-KEY frolicking around on the beach during the day and then lighting up sparklers at night, perfectly fitting the song’s summer vibe. The video ends on an emotional note when the song fades out with the song’s signature guitar riff and piano, showing a mysterious woman flipping through a book, presumably reminiscing about the past. Then, HWISEO sits down with her, and they share a laugh, closing on a positive feeling.

With Lovestruck out now, H1-KEY sat down with Stardust to learn how “Summer Was You” resonated with them, as well as what the group’s activities are for the rest of the year.

Your latest single, “Summer Was You,” has a very infectious and catchy chorus. Can you go into why the song resonates with H1-KEY? What are each of your favorite things about the song?

RIINA: If you focus on the lyrics, they really fit with what we usually do. It’s something that we’ve never tried before, but we’re really confident in doing this song..

YEL: It really fits with the season, and I believe that we can make it feel more cool with the sound.

SEOI: Even though it’s really cheerful, you also have this kind of nostalgic warm feeling to it, but depending on who listens to it, they can feel it differently.

Your fourth and latest mini album, Lovestruck, is a much more vibrant-sounding project than last year’s LOVE or HATE mini album, which I found to have a more sultry and mature sound. How do you decide on what sounds to experiment with and how?

SEOI: Typically, when we look for a song, we want to see if it can fit with H1-KEY, and if there’s any message that we can convey with it. The image can change according to the song. Last time, we were more mature but this time, we were summery. And so that's why we decided to do “Summer Was You,” as it really fit with the season.

I’ve seen a lot of promotions for “Summer Was You” on social media, especially on TikTok and the dance collaborations with other groups. Can you offer some insight on how collaborations work?

SEOI: If we’re talking about TikTok, then if we have friends who are also doing activities, we’ll tell them, ‘Hey we’re coming back. We have this song, do you want to do [this collaboration] with us?’ But if it’s someone else that we don’t really know, or a senior, we go through the company. Especially because now TikTok is a whole different platform, it’s not something that you just do between friends anymore. Generally, the companies will talk about it with each other.

Since your debut in 2022, how do you think H1-KEY has grown as a group?

HWISEO: Aside from identity and our sound getting more apparent with our releases, as we’ve kept going on stages, we also grow as artists. Let’s say we make a mistake on stage, as professionals, we now know how to make good of it.

SEOI: Mostly, we have to be flexible and take care of a mistake as fast as we can without drawing attention to it. Let’s say we make a mistake in a movement, then we’ll just go to the next movement without making that visible. But if it’s something that we have to help each other with, we’ll help each other. The most important thing is that we don’t want to make it apparent because if it’s obvious, then people who watch it will also see that we made a mistake.

What are some of your favorite K-pop songs right now that you’re listening to?

YEL: You know about Kpop Demon Hunters? I really like it and I keep listening to “Soda Pop” and “Golden,” even on my commute in the car and everywhere.

RIINA: Everyone likes “Soda Pop” and “Golden”, but I also really like Aespa’s “Dirty Work.”

SEOI: Illit’s “Do the Dance.” The concept is so cute that I doubt H1-KEY could pull off something like that, and that’s something that I really like.

HWISEO: Of course, “Summer Was You,” but I also like BLACKPINK’s new song, “Jump.”

Are there any particular songs or performances that you’re proud of?

YEL: Looking back at all of the music shows we’ve done, we’re proud of ourselves. The dancing part and the songs are hard to sing. So every single one, and please watch every single performance!

What are H1-KEY's plans for the rest of 2025?

HWISEO: We’re actually having our Japanese debut next month. Aside from that, we’re also going to be performing in a lot of festivals, especially this summer. As for tours, we don’t have any plans right now, but if there are any M1-KEYs [our fandom name] calling us, then we’ll come right away!