It’s unlikely that MI6 or the CIA will be calling Romulo, a private investigator in Chile, to lure away his newest star recruit, but damn, if he doesn’t try to train up the 83-year-old Sergio to be the spy of the highest order in “The Mole Agent.” After receiving a tricky assignment that he’s unable to perform himself – asked by the daughter of a woman at the San Francisco Retirement Home to see if her mother is being mistreated by the staff – Romulo has put a classified ad in the local paper, looking for octogenarians that might fit the bill and coming to find Sergio, a relatively new widower who would appreciate a distraction in the wake of his recent loss.

Director Maite Alberdi brings in a John Barry-esque score and chiaroscuro lighting to set the mood for the espionage thriller that Romulo and Sergio think they’re in, with the former training the latter in the specifics of how to use pens with covert cameras inside and more basic tech like FaceTime, but when Romulo smuggles Sergio into the hospice center, it’s revealed that the sly filmmaker has snuck in an entirely different story than the one that’s been set up. You might have your suspicions from the fact that the San Francisco Retirement Home is filmed more vibrantly than any senior citizens community has ever been put to film, filled with vivid colors such as orange and purple and celebrations galore to capture, leaving little wonder why Sergio, a pretty spry gentleman who blends in with his sharp baby blue blazer, seems to become such an instant sensation there, especially when the ratio of women to men is 10 to 1.

Sergio learns pretty quickly that Marta, his central “target,” hardly seems to be the victim of any impropriety and is largely bed bound, making it so he can turn his attention to any number of other residents at the home, such as Rubira, whose memory is fading, Rosa, who might be stealing from others, and Berta, who becomes so bewitched by Sergio that she begins to literally pick off petals, saying “He loves me, he loves me not.” His attention to them proves rejuvenating, which is why it becomes so curious to him why none of their relatives ever seem to come to visit and despite the ridiculous nature of the premise in which Romulo continually asks, “What’s your QTH?” Sergio’s nightly reports back grow more circumspect and poignant, as he grows frustrated with seeing so many put out to pasture when they have so much life left in them, particularly when he stands as his own example of reinventing himself.

It won’t be surprising when someone snaps up the rights to remake “The Mole Agent” as a narrative feature, given its inspired premise – a second life as a late career Clint Eastwood vehicle seems too obvious a moneymaker – but it would also be completely unnecessary, particularly when Alberdi so expertly crafts the nonfiction film to unfold as a work of drama, skillfully aping spy movies of the past, but additionally capturing moments between Sergio and others at the home that seem too good to be true. There’s no small irony here when it takes the perceived artifice of a movie to get at a reality about aging that most of us would rather not face, but the more Sergio is asked to go undercover in “The Mole Agent,” the deeper it gets for everyone.