Sadie Sink began her acting career on stage, playing the orphan Annie in a regional production in Houston, Texas, before landing a role in the 2012 Broadway revival of the musical. She rose to wider fame as Max Mayfield in Netflix's Stranger Things, a breakout role that established her as one of her generation's standout young actresses.

She has since built a strong stage career alongside her screen work, earning a Tony Award nomination for Best Performance by an Actress in a Leading Role in a Play for her role as Shelby Holcomb in a contemporary adaptation of The Crucible, a production also set to be adapted for the screen with Tina Fey producing and Sink attached as an executive producer. In Spider-Man: Brand New Day (2026), she plays Jean Grey, joining Tom Holland's fourth standalone outing as the web-slinger alongside Zendaya and Jacob Batalon, in a performance noted for its range between explosive intensity and quiet vulnerability.