Each of director Damien Chazelle's last three feature films end with two people exchanging a loaded glance. In Whiplash (2014), the lines on a sadistic music teacher's face briefly curl into evidence of respect for a student who, by the end, manages to beat him at his twisted game. In La La Land (2016), two former lovers share a look of resigned longing from across a bar. In both movies, the protagonists want the same thing — the pursuit of artistic excellence unites the musicians, the couple is still in love — but the framing makes it clear there's an invisible barrier between them they can't surmount. The last shot of First Man (2018) subverts this by having a very literal barrier between its two protagonists, despite which they reach out and share a real moment of human connection.
For most of the Neil Armstrong biopic, the astronaut (Ryan Gosling) and his wife (Claire Foy) are reeling from the loss of their two-and-a-half-year-old daughter. As he grows increasingly uncommunicative and distant, the chasm between them grows to cosmic proportions. It takes Neil a trip to the moon to attain catharsis. When he returns, the reflection of his wife's face on his in this shot indicates that they're finally on the same side. Earlier in the film, the two hold hands across a dinner table when Neil gets the call informing him he's been selected for the spaceflight program Project Gemini. He asks his wife if she's sure he should take the job. "It'll be a fresh start," she responds. That's exactly what the last shot of the film feels like.