For fans of the genre, IMDb users’ scores have made it easy to determine the best sci-fi movies of all time. Jurassic Park is nothing short of one of the best films of the 1990s, a gem that remained the highest-grossing film of all time for four years and is still one of the highest-rated on IMDb. As it turns out, it's not just the mainstream movies on IMDb's official Top 250 highest-rated movies that are among the highest-rated sci-fi films on the site: There are also masterpieces as criminally underappreciated as the Hungarian adult animated gem Cat City, which still doesn't have enough user ratings to enter the official IMDb Top 250.