“At rare intervals,” fellow blacklisted screenwriter Ring Lardner Jr. intoned during his eulogy at Dalton Trumbo’s funeral in 1976, “there appears among us a person whose virtues are so manifest to all, who has such a capacity for relating to every sort of human being, who so subordinates his own ego drives to the concerns of others, who lives his whole life in such harmony with the prevailing standards of the community, that he is revered and loved by everyone with whom he comes in contact. Such a man Dalton Trumbo was not.”

Though tonally short on the irreverence that characterized its subject’s funeral, director Peter Askin’s documentary “Trumbo,” which opens in the city on Friday, takes a polished and partisan look at a life and career that became contentiously politicized when Trumbo appeared before the House Un-American Activities Committee in 1947. Prior to his testimony as an “unfriendly witness,” Trumbo, who was born in rural Colorado in 1905, had grown from magazine writer to successful novelist to highly sought screenwriter in a relatively short span. But when the committee’s chairman, J. Parnell Thomas, administered the oath to Trumbo, as he did to many suspected left-leaning members of the fledgling Writers Guild of America, Trumbo’s Communist Party affiliations were unmistakable.

In spite of the subsequent loss of Trumbo’s livelihood and stature (“He probably was the best writer of that time,” Kirk Douglas offers, not inaccurately, in an interview), not to mention the aftereffects of a seminomadic existence with his family and the injustice of seeing his work produced under assumed names, “Trumbo” clearly proves that, if nothing else, its subject endured the deprivations of the blacklist with more wit than any of the rest of the writers in the original Hollywood Ten.

“Get ready to become nobody” is how Trumbo describes the process of divestiture that followed his HUAC adventure. But during what’s portrayed as a boozy and increasingly desperate 1950s exile in Mexico, along with a small community of fellow blacklisted writers, Trumbo’s authoring of dozens of films under a variety of disguised credits forced him to become multiple nobodies.

Rather than showcasing clips from such Trumbo-scripted masterpieces of low-budget storytelling as “The Brothers Rico” and Joseph Lewis’ brilliant “Gun Crazy,” Mr. Askin, in collaboration with Trumbo’s son, Christopher, who himself produced a stage work about his father’s life and legacy, opts for talking-head footage culled from interviews with Trumbo, his family, his friends, and his colleagues. But the most eye-opening and memorable element of the film is the series of performances, by Donald Sutherland, David Strathairn, Paul Giamatti, Josh Lucas, Michael Douglas, and others, of Trumbo’s written works and personal correspondence to debtors, family friends, enemies, and colleagues.

In these sequences, Trumbo’s easy wordplay and marvelous ability to stack adjectives into stone walls of well-reasoned irony receive interpretations of wide-ranging facility and acuity. Mr. Giamatti sinks his teeth into a series of notes regarding overdue bills to the phone company, in which Trumbo at one point reminded the utility that instead of taking the threatened immediate action, “considering what you’ve done to me, you ought to wait the full nine months.”

Joan Allen’s reading of a letter to the parents of one of Trumbo’s deceased war-era friends is a performance of precision and emotional agony. It’s nice to be reminded that the actress is equipped to knock one out of the park when the material is worthwhile.

Eventually, after earning an Academy Award under an assumed name for 1956’s “The Brave One,” and finally receiving screen credit thanks to director Otto Preminger and producer Kirk Douglas, Trumbo’s 13-year professional banishment ended and his employability, credits, and reputation were restored. “I’ve now realized it was all one fight,” the author says late in his life and late in the film. After watching “Trumbo,” one suspects that no matter when he was born, Trumbo’s flair for agitprop and almost compulsive iconoclasm would have brought him into conflict with the prevailing politics of any era.