Hootie & the Blowfish are headed to Las Vegas in September. The recently reunited '90s rock back have joined the lineup for the 2019 iHeartRadio Music Festival.

In addition to Hootie & the Blowfish, fronted by now-country star Darius Rucker, Marshmello, Steve Aoki and special guests Darren Criss and Monsta X have joined the multi-genre music festival, set for Sept. 20-21 at Las Vegas' T-Mobile Arena. Previously announced acts for the event include country artists Tim McGrawMaren MorrisZac Brown BandBrett YoungOld Dominion and Miley Cyrus. Additionally, the lineup features Alicia Keys, Cage the Elephant, Camila Cabello, Chance the Rapper, Def Leppard, French Montana, Halsey, Heart, H.E.R., Mumford & Sons and more.

Ryan Seacrest will host the 2019 iHeartRadio Music Festival, which will also feature an outdoor Daytime Stage at the Las Vegas Festival Grounds on Sept. 21. The festival will be broadcast live in iHeartMedia's more than 150 radio markets, and the CW TV network will broadcast a two-night special featuring performances from the event on Oct. 2-3 at 8PM ET.

Hootie & the Blowfish are currently on the road for their Group Therapy Tour. The band announced their reunion in late 2018, also sharing that they'd signed with UMG Nashville — Rucker's label home — and are working on new music. They're celebrating the 25th anniversary of the release of their classic album Cracked Rear View in 2019.

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