Susan Morgan’s An Unlikely Weapon: The Eddie Adams Story has an aesthetic blandness that would likely have turned off its subject, the famed photojournalist behind the iconic, Pulitzer Prize-winning 1968 snapshot of Saigon police chief Nguyen Ngoc Loan executing a Vietcong soldier. Many, including Tom Brokaw and Peter Jennings, contend that picture helped end the Vietnam War by bringing home the brutal, horrific awfulness of the conflict. And though Morgan’s non-fiction techniques are only serviceably straightforward, the director engagingly makes clear that Adams’ most renowned image haunted him but did not, ultimately, define his work, which eventually included photos from thirteen wars, of six United States presidents, and of virtually every notable culture figure from the past fifty years. A cantankerous “pain in the ass” who started with the AP and ended as an independent entrepreneur, he was an individual who lived life on his own terms, and whose career embodied the notion that greatness isn’t found in the attainment of perfection, but in the striving for it.

Forgoing background on Adams’ upbringing, Morgan begins her biographical story (narrated by Keifer Sutherland) in ‘Nam, where his brash, gung-ho, coach-like attitude endeared him to the troops and resulted in a series of stunning photographs culminating with the shot of the murder perpetrated by Loan, a picture he derided as not very good and whose impact he later claimed to not fully understand. As confirmed by the comments of friends, colleagues and admirers, others most certainly did comprehend the power and significance of Adams’ signature work, and also the abundant talent the man possessed. An Unlikely Weapon employs its talking heads, archival film clips, and both photos taken by, and interviews with, Adams (who died in 2004 of ALS) to paint a reasonably evocative portrait of the artist as a take-no-shit iconoclast. A contradictory personality drew him to both victims of combat and larger-than-life despots – in one amusing anecdote, he refuses to take guff from Fidel Castro and winds up going duck-hunting with the Cuban dictator – and, once he tired of covering wars, he segued smoothly into a more laid-back celeb-focused second career as a hired gun for, among other publications, Penthouse and Parade magazines.

An Unlikely Weapon’s reverence for Adams is complemented by a refusal to shy away from his often-difficult, combative personality and his habitual self-criticisms, the latter of which suggest the constant determination to be better that typically distinguishes the preeminent from the merely good. Though clips find Adams both discussing the Loan photo as well as describing his reunion with the officer years later in the man’s Virginia pizza parlor, Morgan never quite fully expresses the complicated central role that the photo played in Adams’ life, a shortcoming due in part to the fact that she’s forced to rely mostly on archival interviews for his first-hand thoughts. Still, touching upon the subsequent 1977 pictures that helped convince President Carter to grant Vietnamese refugees entry into the country, as well as the human rights book “Speak Truth to Power” he made with Kerry Kennedy, the film conveys the deep humanism of his work, an abiding compassion and respect that, ultimately, can be felt in everything from his close-up of a somber Vietnamese child to the back-turned photo of Clint Eastwood that graces the poster for Unforgiven.