“There Is a Stone,” Tatsunari Ota’s debut feature, is a curious form of escapism. It’s a film in which very little happens; even the slow-moving cinema of Kelly Reichardt or Eric Rohmer feels hectic in comparison. When I watched it on a screener at home, I paused it halfway through to take a nap. That isn’t a criticism, by the way.

For an extended stretch, the film’s two main characters engage in the kind of idle play that could keep young children occupied for hours. They skip stones on a river, stack rocks and parade around with pieces of driftwood. Yet they are adults who’ve only just met and whose reasons for engaging in such innocent rituals are hard to parse.

One is a young woman from out of town (played by An Ogawa); the other is a burly local man with a childlike demeanor (Tsuchi Kano). Once the game starts, he’s reluctant to let it finish — especially since he’s determined to retrieve a stone that his new companion had gathered, only for him to mistakenly toss it into the river.