It typically takes actors time to ascend to the A-list, and their path up the Hollywood ladder often includes numerous forgotten roles. In fact, today's current crop of stars includes a lot of great actors you forgot were villains on TV. It's a common stepping stone: Before you get the central role or a shot on the big screen, a TV villain is a great way to show off what you can do (or at least pay the bills between other parts). Plenty of movie stars got their start as blockbuster villains, and seeing a recognizable face threatening a hero adds an unexpectedly fun element to a rewatch.
Over the last few decades, networks have produced classic TV villains year in and year out, but case-of-the-week-style shows have also given up-and-coming actors credits that help get their foot in the door. Whether it's Pedro Pascal going from a vamp on Buffy to the (hidden) face of The Mandalorian, or Rami Malek putting a cookie-cutter role on 24 behind him to win Emmy and Academy Awards, some of the most successful actors on Earth paid their dues as TV villains before finding their big break.