It was unfinished business from the brutal days of communist show trials that sparked the idea for “Old-Timers,” a Czech story of cross-country vengeance perpetrated by two actors in their golden years.

Martin Dusek and Ondrej Provaznik, whose documentaries “A Town Called Hermitage” and “Coal in the Soul” both took on the legacy of the pre-Velvet Revolution regime in different ways, say their feature debut was driven by the same desire to deal with crimes that too few people are willing to talk about these days.

The political prosecutions of the 50s are “crimes that are important to these guys but nobody else cares about them,” says Dusek.

In “Old-Timers” Vlasta and Tonda don’t believe they have much longer to live but they do have one more important task ahead of them, say the filmmakers: To find and kill the communist prosecutor who sent them to prison in the 1950s. Things don’t go quite as planned, needless to say.

Jiri Schmitzer, 69, and Ladislav Mrkvicka, 80, play Czech retirees who are not quite world-class assassins, of course, but they do their best to gear up for the job, blasting away at a mannequin standing rather close with pistols they fire from an old van they’ve kitted out for the killing.

Meanwhile, the two grumpy protagonists argue and complain, Vlasta sleeping poorly with nightmares of the old regime’s injustices, which have driven him to recruit his old friend Tonda so they can realize his final wish for revenge.

The relevance of the story is clear at a time when the current Czech prime minister, media mogul Andrej Babis, stands accused of having a secret history of collaborating with the StB, the former secret police, an allegation he refutes. Yet it took a decade to get the project funded, Dusek says. “Luckily it’s relevant still.”

The landscape the would-be assassins roll through on the hunt speaks volumes about the moral outrage that drive the pair, says Dusek – sometimes crumbling buildings that reveal a rotten core, sometimes newly built, all-too-cheerful development projects designed to help people forget the ugly past of the Czech lands.

Even lyrical countryside vistas take on an ironic meaning when contrasted against the bitterness of those who found themselves fodder for a self-proclaimed regime for the working class that needed enemies to punish to sustain itself.

Called by Karlovy Vary fest programmers “at times poetic, at others absurdly humorous,” the directors have also been credited with a cinematic look at the past that “provides a portrait of the stubbornness of age.”

Co-director/co-writer Provaznik says the actors, who enjoy a great deal more renown in the Czech Republic than the filmmakers, were not just stubborn on screen. “At times it seemed they had a conspiracy among themselves to ignore what we were asking them to do.”

In the end, Mrkvicka and Schmitzer, who is also a Bohemian rock star, agreed to go along with the first-time feature directors’ ideas, allowing the long quest to finish the film to finally resolve, says Dusek. But his idea that a narrative film would be easier to make than documentaries about unruly subjects was quickly dashed, he admits.

“Unfortunately you still have to work with actors, who can be just as impossible to control,” he says, laughing.