When does youth end and adulthood begin? After watching dozens of seishun eiga (“youth films”) in which high school kids give up a beloved sport or activity to cram for college entrance exams, I have come to think that, for many in Japan, youth in the free and footloose sense comes to a shuddering halt at age 16.

In Atsuro Shimoyashiro’s “The Modern Lovers,” however, the 30-year-old salaryman Tatsuo (Ryu Morioka) is still clinging to his youth — or rather his illusion of it. Bored with his job and marriage, and stuck in the backwoods of Gunma Prefecture, he plots a temporary escape to Tokyo where once upon a time he wrote scripts, made films and found love. He hopes to recapture some of that lost glory and passion, while knowing he can’t ditch his present existence entirely.

If this sounds pathetic, it is. Tatsuo is less an artist manque agonizing over imagined masterpieces, than a conventional sort who deluded himself into believing he could turn a flurry of youthful creativity into a career. A sympathetic type he is not.