In the meantime — early in the fourth chapter — a character will show up who looks a bit like him and who happens to be a filmmaker working on a multipart project graphically represented by a spider. Though one of the crew thinks it looks more like an ant.

All of the films within the film — except for the fifth one, and significant parts of the third and the fourth — star the same quartet of women. Their names are Elisa Carricajo, Valeria Correa, Pilar Gamboa and Laura Paredes, and you are likely to miss them when they’re not onscreen. They play scientists, chanteuses, international assassins, 18th-century seductresses and also actresses appearing in the film “The Spider,” which is and is not a parody and a companion piece to “La Flor.”

Are you still with me? Staying with “La Flor”— which is being shown in theaters in four parts, each with at least one intermission — requires effort as well as stamina. The first two chapters, a quasi-horror film about a mummy and a musical melodrama about battling divas and renegade scientists, are compact and satisfying, even though each one ends abruptly in the middle. (That’s not a spoiler. We’re warned about this at the outset).

Chapter three, also inconclusive, is one very long middle, or maybe a clump of middles, like a breadless club sandwich. It’s an espionage thriller of the kind that, according to the director, “the Americans used to make in their sleep.” Maybe so, but Hollywood has always preferred if audiences stayed awake. The tension that the first chapters so deftly built up and manipulated is allowed to dissipate. I don’t think this is an accident, but rather an experiment. What if a story slowed down when we wanted it to speed up? Would we still be interested?

Chapter four adds a metaphysical dimension to the inquiry, inviting us to care (or not) about situations that may only be the figments of fictitious characters’ imaginations. This can be enjoyable as well as exasperating, and part of Llinás’s intention seems to be to explore the boundary between those two states.