On this day, Sept. 11, in hip-hop history...

Shady Records / Aftermath

2007: 50 Cent got experimental when he dropped his third studio album, Curtis, on Sept. 11, 2007.

Coming off the massive success of his sophomore album, The Massacre, in 2005, the South Jamaica rapper-turned-household name wanted to take his time and try something different with his music. Curtis featured production from the likes of Dr. Dre, Eminem, Havoc and Timbaland and guest vocals from new collaborators like Akon, Justin Timberlake and Mary J. Blige. The combination of pop-leaning rhymes and Fif's signature hard-hitting street bars were met with mixed reviews among critics, but fans of the Queens rapper remained faithful.

Propelled by club banger singles like "I Get Money" and "Ayo Technology" featuring Justin Timberlake and Timbo's futuristic production, the LP debuted at No. 2 on the Billboard 200, moving 691,000 copies in its first week.

This album also marked the historic head-to-head release day battle between 50 and Chicago rhymer Kanye West. After years of dwindling album sales in the music industry in the early aughts, 50 Cent's Curtis and Kanye West's third album, Graduation, ignited a debate in the rap world and a media whirlwind.

At one point, Fif even said he would retire if Kanye's album sold more than his. The two MCs' race to release day came to be known in the media as the Soundscan showdown and resulted in record breaking performances. That week marked the first release date in 16 years that two albums sold more than 600,000 in a week in the U.S.

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