There’s nothing like a bit of time travel to give you some perspective on a relationship. Kanna (Takako Matsu), a 45-year-old widow, is driving along the Shuto Expressway in Tokyo one night when she finds herself transported back to the summer’s day 15 years earlier when she met her future — and late — husband, Kakeru (Hokuto Matsumura).

He doesn’t recognize her, of course, but they hit it off anyway — all of which is a bit complicated. Kanna knows that Kakeru will be meeting her younger self later that day. She’s also aware that their marriage won’t work out. The couple will sign their divorce papers on the morning of Kakeru’s death, in a train accident that provides the bracing curtain raiser for Ayuko Tsukahara’s “First Kiss.”

On discovering that her journey back to that fateful day can be repeated, Kanna keeps returning for more, trying to change the course of events that led to Kakeru’s demise. She plots out alternate timelines at home, using strings of sticky notes hung from the ceiling: Maybe she can save him if she prevents him from stopping off at a croquette shop before the accident, or steers him onto a different career path?