Great sci-fi shows are no exception. Maybe you’ve been meaning to check out a long-running genre entry like Stargate SG-1on Pluto TV for free to ensure uninterrupted viewing. Alternatively, a show like Snowpiercer might catch your attention, prompting you to check out all four seasons on Roku. But there are even better shows out there that you can watch without paying for a subscription. Here are the five best sci-fi shows you can stream online for free.