Kohei Igarashi’s “Super Happy Forever” is bitter and sweet, in that order. It’s a love story that starts at the unhappy end and then flips back to the beginning. That might sound like a recipe for ruefulness, yet this isn’t a bummer in the vein of nonlinear romantic dramas such as Derek Cianfrance’s “Blue Valentine” (2010). Rather, it’s a reminder that our past happinesses still count for something, even if they prove fleeting.

The melody of Bobby Darin’s 1959 signature hit, “Beyond the Sea,” echoes through the film. It’s a song about yearning for a distant lover (“We’ll meet beyond the shore / We’ll kiss just as before”), but the lyrics take on a more melancholy resonance here.

There’s nobody waiting for Sano (Hiroki Sano) when he returns to the seaside hotel where he first met his wife, Nagi (Nairu Yamamoto), five years earlier. The setting is a faded beach resort on the Izu Peninsula, once a popular destination for honeymooning couples. But the hotel is now on the verge of closure, while Nagi has recently died.