Hello,
being a non-native speaker, I used in the past and I continue to use films and TV series to improve my listening skills. However, I suggest this method only to upper-intermediate or advanced students who own enough vocabulary and listening skills to understand at least the gist of what you are watching. In this case, my suggestion is to alternate watching these film with subtitle at the beginning, then try to take out them to test whether your listening skills have improved or not. If you start from scratch, based on my personal experience, podcasts for your level are a much better alternative to film and TV series.