Caleb Williams is following his coach to Hollywood.

The star Sooner, the freshman phenom, the Heisman hopeful, the proverbial bell of the transfer portal ball, and one of the most exciting young quarterbacks in the country is coming to USC. Williams will reunite with Lincoln Riley, the coach who recruited him from the Washington D.C. area in the 2021 cycle and handed him the keys to the Oklahoma offense at the Red River Showdown.

Finally, USC has its quarterback.

Williams signed all of his paperwork to attend USC late last week, according to ESPN, and registered for classes on Friday, ahead of the school’s final deadline to do so. He’s expected to attend his first class at USC in person on Tuesday and be cleared to join team workouts in the upcoming days, according to ESPN.

“I want to get to work right away, earn the trust of my teammates, win championships and help bring USC back to being a top-rated program,” Williams told ESPN’s Pete Thamel.

Nothing short of talking about the College Football Playoff is too hyperbolic to describe what Williams’ decision means for Riley and USC in the immediate present. When Riley first arrived at USC, he talked about immediately stripping and rebuilding a roster that had a ways to go before becoming one of college football’s elites.

“We’re getting ready to, in a lot of ways, overhaul this roster. Today is one step in a process,” Riley said during an appearance on the Pac-12 Network for the Early Signing Period. “When you’re getting ready to turn over the number of spots we’re getting ready to turn over, there’s an understanding that it’s a process.”

Riley has been forthcoming with the roster, and the transfer portal has seen a good deal of USC players enter into it since he took over. That included both quarterbacks who started for the Trojans in 2021—Kedon Slovis and Jaxson Dart.

Slovis’ departure wasn’t as surprising as Dart’s.

Dart was a former 4-star and top-100 player, per the 247 Composite, in the Class of 2020. He was the national Gatorade Player of the Year as a high school senior, and then threw for 1,353 yards and nine touchdowns this past season in six appearances. Dart completed 62% of his throws and tossed five interceptions in 189 attempts. When Slovis was injured earlier in the season, Dart took over and showed promise as a young quarterback.

But his decision to enter the portal weeks ago (he landed at Ole Miss) signaled one thing: Williams was coming.

And if Williams was coming, Williams would start.

The freshman entered the transfer portal on Jan. 3, just a few days after beating Oregon 47-32 in the Alamo Bowl. He was electric that day, going 21-for-27 on his pass attempts for 242 yards, three scores, and no interceptions. After, Williams raised eyebrows by saying, “We’ll see how Oklahoma does and how I decide,” when he was asked about his future with the program.

Williams was the seventh-ranked player overall in the class of 2021 and the second-ranked quarterback prospect, per the 247 Composite. He committed to Riley and OU during the extended recruiting dead period brought on by COVID-19, and when his senior season in D.C. was canceled, he and his family moved to Oklahoma to allow him to enroll early for the spring semester at OU, according to The Athletic’s Jason Kersey.

A key reason for his initial commitment to the Sooners: Lincoln Riley. Williams once said he would have walked on at Oklahoma to play for Riley. Of course, he didn’t have to, but he began his first year in the program as the backup to Spencer Rattler. Williams took the starting job midway through the year thanks to an incredible display of passing and a 21-point comeback win he spurred over Texas, and he never gave the job back. Rattler transferred to South Carolina after the season.

The Sooners overcame a 28-7 deficit after the first quarter that day at the Cotton Bowl against Texas, matching the second-largest comeback in program history, and Williams was the driver. He ran for a 66-yard touchdown on a fourth-and-1 and completed 15 of his 24 passes for 211 yards and two touchdowns—including a 52-yard bomb—after replacing Rattler, who had two turnovers in the first half that led to Texas touchdowns.

From then on it was the Caleb Williams show. And the Sooners seemed to have new life as a team. Oklahoma was in the hunt for a CFP berth until the final week of the regular season, a 37-33 loss on the road to Oklahoma State.

Williams was named to the 247Sports and ESPN True Freshman All-America teams after throwing for 1,912 yards, 21 touchdowns, and just four interceptions. He also ran for 442 yards and another six scores. He finished the season fourth nationally in total QBR (86.5), behind Ohio State’s CJ Stroud, Alabama’s Heisman Trophy winner Bryce Young, and Georgia’s national title winner Stetson Bennett.

His 247 evaluation as a recruit was glowing:

“Has one of strongest arms in ’21 class. Throws well in rhythm but has to be more consistent with accuracy when getting through progressions. Feels pressure and has ability to escape. Strong leadership qualities and makes plays in big spots. Plays with creativity and can make defenses pay when play breaks down. Can change games with feet and arm. Makes off-platform throws look routine.”

Williams immediately elevates the Trojan offense.

With 5-star running back Raleek Brown and high-4-star wideout CJ Williams joining the program as Class of 2022 signees, Washington transfer and big-play threat Terrell Bynum coming in from the portal alongside Colorado youngster Brenden Rice, Oklahoma wideout Mario Williams, Stanford running back Austin Jones, and the Pac-12’s reigning leader in yards from scrimmage in Oregon’s Travis Dye, there’s reason to be excited about Riley’s first year.

With a quarterback in tow who already has an established relationship with the head coach and a comfortability within that coach’s offense, Williams should be able to step right in and get to work building chemistry with his new crop of receivers and backs.

It could be a young offense in 2022—though that doesn’t figure to cap the ceiling—but it doesn’t necessarily have to be. Brown forecasts as a do-it-all kind of weapon, a matchup nightmare Riley can play with all over the board. If he earns playing time alongside the likes of Dye and Jones, it’s because he’s ready to make an immediate and high-level impact. If Dye wins the starting job, that’s a nice option to have in the backfield next to a growing quarterback; Dye totaled 1,673 yards from scrimmage and 16 rushing scores in 2021 with Oregon.

The two Williamses at wideout offer complementary skillsets that should give their quarterback plenty to work with. The incoming freshman, CJ, is a strong route-runner with a big frame. The transfer, Mario, is as sure-handed as they come with big-play and quick-twitch abilities. Rice looked like Colorado’s most important offensive player last season.

What Riley has been able to put together at USC in short order is nothing short of spectacular. And Caleb Williams brings it all together.

“I think those of us that have followed college football for a long time have a great appreciation for what USC can be, has been, and what I fully believe will be again,” Riley said during an appearance on ESPN’s College GameDay ahead of the Rose Bowl. When this program is rolling, when it’s operating at a high level, I really believe there’s none like it in the country. But it’s our job to not just rely on the past, not just rely on the logo, we’ve got to go make it happen right now, and that’s why we came.”

For Riley to get things rolling immediately, he needed to find his quarterback.

Mission accomplished.