The show kicks off its second season with a ratings boost fueled by a strategic summer run of its first on the streamer.

Riverdale, The CW's teen noir about those once-wholesome Archie comics characters, managed a feat no other returning series has accomplished this season: Live ratings for its Oct. 11 sophomore premiere grew an unprecedented 60 percent from its launch nine months earlier.

It's the first ironclad evidence of a linear windfall that broadcasters have hoped for since studios started making deals to put current series on streamers (Netflix, Amazon and Hulu) for the off-season.

As soon as Riverdale's first season concluded, all 13 episodes dropped on Netflix — where, sources say, it was a summer breakout. But that success presented an obstacle.

"Probably more people watched it on Netflix thinking it was a Netflix show," says The CW executive vp marketing and digital Rick Haskins. "Our real challenge was taking those viewers and moving them over to The CW."

Haskins and his team did that with a slightly bigger marketing campaign for a second-year show, one that hinged on the simple pitch that new episodes are "only" available on The CW and its app. Viewers appear to have gotten the message.

After 24 hours on its own streaming site, the Riverdale season-two premiere already ranked as the most streamed episode in the platform's history. And, with live-plus-3 ratings moving the linear haul 44 percent above the previous high to 3.3 million viewers, it seems clear who exactly was catching up on Netflix: Riverdale's teen audience is up 400 percent.

This story appears in the Oct. 18 issue of The Hollywood Reporter magazine. To receive the magazine, click here to subscribe.