James Corden has another viral hit on his hands. The latest "Carpool Karaoke" segment featuring recording artist Gwen Stefani along with special guest appearances by A-list actors George Clooney and Julia Roberts, is amassing huge numbers of views on YouTube, enough to beat out initial views of Justin Bieber's segments but not the most popular "Carpool Karaoke" segment ever featuring Adele.

Recently we brought you the news that Corden's regular feature on his CBS "Late, Late Show" had accumulated a whopping 1 billion plus YouTube views. The clips are so popular that Corden was given a primetime special on CBS recently which featured them, and a separate series based on the concept is in the works for the host. We also told you that the most popular of all the "Carpool Karaoke" segments was the one featuring UK singer Adele, followed by three separate rides all featuring pop star Justin Bieber.

It looks like the Biebs could be in for a challenge, however, as Corden brought out some big guns for the latest clip. First, Gwen Stefani rides shotgun solo with Corden, singing along with him on some of her most famous solo and No Doubt hits, including "Don't Speak," "Rich Girl," "The Sweet Escape" and the current "Used To Love You."

Things get really interesting when the two hit the carpool lane and need more passengers. Corden makes a quick call and none other than George Clooney shows up, and then recruits his pal Julia Roberts to join him in the back seat. After a rousing version of Stefani's "Rich Girl" by the foursome, they break into an anthemic rendition of Queen's classic "We Are The Champions" to cap off the ride.

The combination of star power translated into heavy early YouTube and Facebook viewership, which totaled over 19 million in the first four days the clip was available. That didn't threaten Adele's record of 34 million views in its first four days, but shattered Justin Bieber's second place 13 million for his first ride, and looks like when all is said and done the Stefani/Clooney/Roberts clip will replace him as the second most viewed "Carpool Karaoke" video ever. That is until Corden brings out the next big stars who will join him for a ride. With some of the biggest stars on the planet having already shown up, there's no telling who might be next.