Netflix’s Witcher series could premiere in 2020 writer reveals Netflix‘s adaptation of The Witcher book series has been in development since May of last year, and while things continue to chug along for the epic fantasy series, we may finally know when to expect it. Executive producer/writer Lauren Schmidt Hissrich has taken to Twitter to confirm a few more details on the series and among them are the potential premiere window of 2020. RELATED: Witcher Characters Confirmed for the Netflix Series “Who knows?!