This review may contain spoilers. I can handle the truth.
Chris Allen’s review published on Letterboxd:
This review may contain spoilers.
There's a picture on the cover (<-- right over there) that sells this film seem as a romantic comedy, but it's really something else. The relationship story between Gleeson and McAdams is fun and exciting, but this story isn't truly about them. It's about dealing with death.
While his time travel power is thankfully never really shown to be used to take advantage of any woman, (have you seen Love Actually?), his use of it to cheat death and spend an unlimited amount of time with his father and coming to terms with that ability ending, and the finality of his father's death, is the real theme here. It's about taking advantage of the time we have.
And it's those final scenes with Nighy and Gleeson that always get me in an emotional mess. When father and son sneak out one last time to play on the beach, as Gleeson is now so far back in time that he has become a child, it really hits me: I'm at that age where the boy could be me, side by side with my aging father, and also I could be the father, wishing to spend time with my son again at that age. That focal point of being between both of those characters as they share this final act, is overwhelming.