In Episode 7 of HUMANS, Niska finally reaches the end of her journey and comes face-to-face with the Synth Who Sleeps.

What she discovers shocks her -- just as it shocked the cast and crew in real life when they first learned about Odi's return.

Go Inside Episode 7 With the Cast and Creators

"We talked a lot about who would be the Synth Who Sleeps," says producer Vicki Delow. "We were really sad that we couldn't find a story for Odi as the character he was. And Sam and Jon had this brain wave of bringing the two things together," she explains.

"When I read the episode where [Odi] comes back, I gasped out loud," says Emily Berrington. "I couldn't believe it. We were all so suprised, that was kept completely secret from all of us," she adds.

Click here to go inside the reveal of the Synth Who Sleeps. Plus, the cast and creators discuss how spirituality affects Synth’s relationships with humanity and their search for meaning in life.

Watch the full Season 3 of HUMANS now on amc.com and AMC apps for mobile, Fire TV, Xbox One, Apple TV, Roku and Chromecast.

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