Showrunners Lisa Joy and Jonathan Nolan have a pre-existing deal in place that keeps them with the sci-fi drama for up to six seasons.

Westworld will reanimate at HBO.

The premium cable network has renewed the sci-fi drama from Lisa Joy and Jonathan Nolan for a fourth season. A return date for the series has not been determined after the VFX-heavy series starring Evan Rachel Wood, Thandie Newton and Jeffrey Wright was off the air for nearly two years between seasons two and three. An episode count has also not yet been determined. (Seasons one and two ran 10 episodes each, while three consists of eight.)

"From the Western theme park to the technocratic metropolis of the near future, we've thoroughly enjoyed every twist and turn from the minds of master storytellers Jonathan Nolan and Lisa Joy," HBO programming president Casey Bloys said Wednesday in a statement announcing the pickup. "We can't wait to see where their inspired vision takes us next.”

The renewal comes as little surprise as Westworld remains a key piece in HBO's scripted originals lineup. While season three returned down (1.7 million total viewers, including 901,000 linear vs. 2.05 million of the latter in season two), the renewal, per sources, was part of Joy and Nolan's larger payout as part of their nine-figure overall deal the duo signed with Amazon last year. While the married showrunners will create new projects for Amazon, the deal included upfront payment for their services as showrunners on Westworld for what sources say could be up to season six.

Joy and Nolan, meanwhile, are already at work on multiple projects for Amazon, including the Warner Bros. TV-produced The Peripheral, which was ordered to series late last year. Writer Scott B. Smith serves as showrunner on that drama series, which is executive produced by Joy and Nolan and based on the book by William Gibson. The season three finale is set to air May 3.

Westworld is from Warner Bros. TV. J.J. Abrams exec produces via his Bad Robot banner, while Joy and Nolan oversee via their Kilter Films shingle. It is based on the feature film from Michael Crichton. Tessa Thompson and Aaron Paul also star.

HBO's scripted originals roster includes Avenue 5, Barry, Betty, Euphoria, Gentleman Jack, Insecure, Perry Mason, The Righteous Gemstones, Run and Succession, as well as Abrams' Contraband and Lovecraft Country, among several others.

For more Westworld coverage, head to THR.com/Westworld.