You definitely won't be asking "Who are you?" after checking out our exclusive first look at the opener for CSI: Vegas.

No revival of CSI is complete without its signature anthem.

EW has the exclusive first look at the title sequence for CSI: Vegas, featuring "Who Are You," the classic song from the Who, plus the faces we're most excited to see: those of Sara Sidle (Jorja Fox) and her onscreen husband, Gil Grissom (William Petersen).

CSI: Vegas
William Petersen as Dr. Gil Grissom and Jorja Fox as Sara Sidle on 'CSI: Vegas'
| Credit: CBS

Creator Anthony E. Zuiker tells EW there would be no revival without Petersen on board. Even then, the charismatic star of the long-running CBS drama wanted to make sure Zuiker would be heavily involved before he signed on to the update, which is also bringing back actors Paul Guilfoyle (who plays Jim Brass) and Wallace Langham (David Hodges).

"We didn't write anything until the deals were done," says Zuiker. "It all hinged on Billy coming back."

CSI first launched on CBS in 2005 and wrapped in 2015 after 15 seasons. Zuiker is still amazed it even had to end six years ago. "Every time I see a promo for Law & Order on NBC, or for Chicago Fire, Chicago Med, or Chicago P.D., I can't believe they took all the [CSI] shows off the air," he says. "NCIS and CSI were the crown jewels of the network. It's a real travesty they all went off so quickly."

At one point, CBS had four CSIs on prime time: the original, CSI: Miami, CSI: NY, and CSI: Cyber. "Once Cyber went down, the castle began to crumble," says Zuiker. CSI: Miami ran from 2002-2012; CSI: NY from 2004-2013; and CSI: Cyber from 2015-2016.

Jorja Fox and William Petersen on 'CSI: Vegas'
| Credit: Sonja Flemming/CBS

The revival, which will also feature new characters played by Paula Newsome and Matt Lauria, is still missing a key component from the original: Marg Helgenberger. "If we're able in the second season to allocate the budget for her to return, that's a place we'd go immediately," says Zuiker.

Still, he thinks he and CBS have exactly what they need to make CSI: Vegas a success. "William Petersen is the glue and the DNA to the entire franchise," Zuiker says. "The totality of the anthology begins and ends with him."

CSI: Vegas premieres Oct. 6 at 10 p.m. ET/PT on CBS — 21 years to the day after it first debuted back in 2000.

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