One of Netflix's most popular TV shows, The Office, is leaving the streaming service for NBCUniversal's rival product in January 2021.

On Tuesday, Netflix tweeted out the news. "We're sad that NBC has decided to take The Office back for its own streaming platform," it said.

In a press release, NBCUniversal said it had secured "the exclusive domestic streaming rights" to The Office. "All nine seasons of this beloved NBC sitcom will be available on the company's soon-to-be-launched streaming service for five years, beginning 2021," the company added.

To watch The Office in 2021, US-based viewers will have to sign up for NBCUniversal's upcoming streaming service, which is set to launch next year. It'll come in two forms. An ad-supported version will be available for free to paid TV subscribers of Comcast Cable and Sky. The second will be a subscription-based product, which will contain no ads.

NBCUniversal's decision to take back The Office isn't exactly a surprise. The company previously mentioned it would retain the rights to "certain titles" for the new streaming service. And according to NBCUniversal, The Office isn't just the most watched TV show on Netflix; it's the most popular show across all streaming video services in general.

The loss of The Office underscores the pressure Netflix is facing to keep viewers hooked; Many of its most popular TV shows and movies are licensed from other companies, which are also preparing to enter the streaming wars and taking their content away.

A big test will occur later this November when Disney launches its own competing product, called Disney+. It'll cost $6.99 a month and feature many Disney-owned shows and movies that Netflix will no longer have the rights to.

In response, Netflix has been investing billions in developing its own original content, including a new TV show, which will star one of the main actors of The Office, Steve Carrell. The upcoming comedy series will be called Space Force and is also being produced by writer Greg Daniels, who helped develop The Office.

This article originally appeared on PCMag.com.