Both David and Kim succeed in portraying the main characters as heroin addicts. Starting from the acting to the body movements and face expressions they were able to make the couple come alive from beginning to end. For me it was a very emotional, deep, and moving performance because I have seen people struggle with opiod addiction before and the scenes where they show withdrawal symptoms were quite accurate. I find these types of movies so romantic because even though they are addicted and struggling every single day to get their fix, they still stand by each other even in their worst times. Finding a partner who would 'ride or die' and stick around no matter what struggles are up ahead is what the majority of us would want and that is pretty much reflected throughout the whole movie. I recommend that you give it a shot, you won't regret it.