Once we catch on that the “Jejune Institute” and its workings are an example of “alternate reality gaming,” and that this documentary is not really an investigation into how gullible San Franciscans became ensnared in a vast conspiracy, director Spencer McCall’s film takes the shape of an amusing portrait of the times. In the words of one participant, it’s “a game that you play by going out in the city and doing things.” Or an elaborate art piece. Or one big scavenger hunt. Or a colossal waste of time for slackers with nothing better to do. Or a way to meet and interact with other people. Pick one, then chuckle along. The graffiti/signage credits sequence is especially fine (92 min.).