Facebook has inked a deal with 20th Century Fox to distribute all seasons of "Buffy the Vampire Slayer," "Angel," and "Firefly" on Facebook Watch.

It's one of the platform's bigger licensing deals and is a departure from Watch's goal of commissioning platform-exclusive programs.

Facebook's strategy with Watch continues to change and is looking more like YouTube's model than other streaming services.

Facebook is hoping that a crop of popular '90s shows can beef up Facebook Watch and the company's big bet on TV-like video programming.

On Friday, Facebook dropped all 268 episodes of "Buffy the Vampire Slayer," "Angel," and "Firefly" on Watch as part of a licensing deal with 20th Century Fox.

Each show has its own Page, and the programming is not exclusive to Watch. The three shows aired on TV between 1996 and 2004, and are also available on Hulu. The drop of the shows comes at the same time that Facebook is widely rolling out its Watch Party feature, which allows people to watch videos together and comment on them in real time.

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The three shows, created by Joss Whedon, "have incredibly dedicated fanbases that have persisted and even grown online," Matthew Henick, Facebook's head of content planning and strategy for media partnerships,told Variety. "What we've been focused on Watch [Sic] is building a people-centric video platform, creating a social viewing experience where you can connect with other people who love the shows, and even the creatives who worked on them."

Facebook's strategy continues to morph with Watch

Watch is a little over a year old but execs continue to switch gears with its big ambitions for video.

Distributing the old 20th Century Fox shows on Watch is another example of how Watch is looking like YouTube and taking pages out of the Google-owned platform's playbook.

After initially pitching Watch as a platform for exclusive shows, Facebook has opened up Watch to include both shows and regular video clips and has also rolled out a self-serve tool that lets creators set up their own Watch shows and get money from ad breaks that run during their clips.

The 20th Century Fox deal also seems to support a recent report from CNBC that Facebook is increasingly focusing on programs geared for older audiences as opposed to the lucrative market of teens and millennials.

This isn't the first time that Facebook has experimented with nostalgia programming. Viacom's MTV Studios and Bunim/Murray Productions are working with Watch to co-produce three seasons of The Real World, another franchise that millennials grew up with. Unlike Facebook's deal with 20th Century Fox, though, Viacom is creating new episodes of The Real World with voting features designed specifically for Watch that will allow users to choose who appears on the show before it airs.