I recommend the movie if you're looking for some drama with even a bit of suspense. The story is well crafted and delivered. They all acted quite well, too. Although, some characters I found rather annoying. I'd still like to clarify that victims of gaslighting aren't just victims. Sad and unfortunate as it may be, the victims play a role as well, by believing too much in that person and doubting themselves, when usually there are signs.
A lot of the times those signs are there from the start. So, let's not sanctify the victims either, please. It's horrible and despicable that anyone would be put through this (the gaslighting), but let's also empower the victims by recognizing their part so they don't make the same mistake, again.