It is obvious that Hanna and Simon, as a couple, have reached the steady state of true love, a deep true love. But it is a steady state... probably too steady. So when each other, separately, meets the handsome Adam, they re-discover passion.
It is a slow movie as we have to discover how the characters are feeling lonely without actually expressing it. Hanna and Simon are a couple but they feel lonely each other. They both meet Adam, on different circumstances, and feel attracted to him. It is true that Adam has everything for him: he is good-looking, he practices some sports, go out, have casual sex... but at the end of the day, he is still lonely. As a proof, his apartment looks like a hospital room.
This movie is about joining each other's loneliness to build a true relationship. But how does it happen? That is the interesting part.
