Karsten Runquist (born October 17, 1997) is a Los Angeles-based filmmaker, YouTuber, and podcast host who analyzes and reviews film and television. He's known for his detailed and varied YouTube videos, which can be serious, fun, or ranty. Runquist also co-hosts the popular movie podcast Karstcast with Jeffrey Borislow, where they've interviewed guests like Elsie Fisher and Emma Seligman.