50 Cent Reflects on 'In Da Club' 15 Years After Its Release (Exclusive)

The multi-platinum rapper looks back on his smash success debut single while promoting his new film, 'Den of Thieves,' in theaters Jan. 19.

When your debut single becomes the most iconic birthday song since "Happy Birthday," you know you've got something special.

ET's Courtney Tezeno spoke to 50 Cent on Tuesday, ahead of the theatrical release of his new film, Den of Thieves on Jan. 19, where he reflected on the impact of "In Da Club," 15 years after the first single off of his monster Get Rich or Die Tryin' debut album dropped.

"It's amazing how fast the times goes," the 42-year-old rapper said with a smile. "It's cool because every day it's someone's birthday."

For those who don't know, this is the song that starts with the lyrics, "Go shorty, it's your birthday, We gonna party like it's your birthday."

50 went on to acknowledge the cultural power of that album for what it was, without seeking to recreate that magic as he gets older.

"Music marks time. We can have new music... this is why I don't like to get in the mix because hip-hop is connected to youth culture," he explained. "You gotta kinda let it trend. You gotta let new things happen."

With that being said, 50 and his Den of Thieves co-star, Gerard Butler, teased a possible music collaboration in the future, something definitely worth getting in the mix!

"I told him I gotta get something of him sampled, a piece of his voice into a record," 50 said with a laugh, with Butler adding, "I want to get up onstage with him and sing a song! I mean, he keeps saying, 'Yeah, yeah, let's do it.' I don't believe him."

"We'll figure it out," 50 assured him.