Real-world heroes don’t necessarily make great movie heroes.

Dr. Bennet Omalu, the subject of the new biopic Concussion, was the first man to publish a study linking head injuries suffered playing football to chronic traumatic encephalopathy (CTE), and his pioneering work as a forensic pathologist deserves recognition and appreciation. But that pioneering work involved things like autopsies, painstaking research, and lots of paperwork — not exactly the stuff of blockbusters — combined with (at least in Concussion’s telling of the tale) a lot of scolding and righteously indignant speeches. This subject is hugely important, but as shaped by writer/director Peter Landesman, it’s not especially cinematic.

The title refers to the film’s subject as well as its style; it hits with the subtlety of an all-out blitz. Everyone says exactly what’s on their minds at every moment, which is usually some kind of overly elaborate metaphor (“It’s tires and oil; it’s mechanics trying to keep the cars on the track,” one team doctor says of his ethically questionable work to keep players on the football field), inspirational life advice (“Need is not weak. Need is need.”), macho posturing (“Get your s— together! You used to be a warrior!”) or vaguely racist and xenophobic threats (“You take your bulls— science and go back to Africa you quack!”). Nothing is left unsaid. Even when the characters in Concussion ask questions, their sentences end in exclamation points.

Perhaps the most telling scene in the film is the one in which Dr. Omalu (Will Smith), who works as a medical examiner for the city of Pittsburgh, receives some advice (more of a lecture, really) from his avuncular mentor, Dr. Cyril Wecht (Albert Brooks). Omalu’s eccentric methods — throwing away his knives after each autopsy, speaking to his “patients” and asking for their help in identifying the causes of their death — make him unpopular with his co-workers. “Be a little bit less of an artist,” Wecht suggests. “Fit in a little more.”

Given that Dr. Omalu’s singular methods eventually yielded one of the most important scientific discoveries in the field of sports medicine, you might expect Concussion to honor Omalu’s eccentricities with a few of its own. Strangely, it instead finds its inspiration in Wecht’s words, shaping Omalu’s unique journey and quirks into a familiar and conventional narrative about a persecuted whistleblower who uncovered a great injustice at great personal cost. The film doesn’t so much tell Omalu’s life story as it nominates him for sainthood. (He certainly spends enough enough time standing in the shadow of crosses to qualify.)

Omalu, a Nigerian immigrant and holder of an assortment of advanced degrees from around the world, barely uses his television and has never watched football when the body of former Pittsburgh Steeler Mike Webster (David Morse) shows up on his table in the morgue. Webster is a local hero and a Hall of Famer, but spent much of his final years in agony, suffering from dementia and living in his car. The coroner can’t understand why an athlete who was only 50 years old, in good health and with no apparent medical conditions would die the way Webster did, so he refuses to let the case go. Despite his colleague’s objections, he orders thousands of dollars worth of tests. Eventually, he finds his answer: the human brain can be concussed with a blow of only 60 Gs, while the average football players gets hit with 120 Gs of force thousands upon thousands of times over a career.

It’s hard to imagine too many filmmakers or studios (several of which are owned by companies that broadcast NFL games) having the guts to make a movie about football and CTE. To Concussion’s credit, it doesn’t soft-pedal the issues or let the NFL off the hook. The league looks like an unfeeling bureaucracy willing to do whatever it takes to protect its considerable financial interests. Landesman lays the blame for the deaths of former players squarely at the feet of executives and doctors who ignored evidence — and possibly covered the evidence up.

But he does so mostly by having Dr. Omalu literally wag his finger in the faces of the NFL stooges who refuse to tell the truth. Omalu is unquestionably right, and the stooges are unquestionably wrong. But once Omalu publishes his preliminary findings, and the NFL brings the full force of their political power against him and his colleagues, there’s not much for anyone in this story to do until more former players die and their brains can be examined for CTE. While the research waits to catch up to reality, Smith has little to play but virtuous fury.

The only scenes that break up the monotony are also the weakest in the film, in which Omalu takes on a female roommate at the behest of his church, and he and the young woman, Prema (Gugu Mbatha-Raw) slowly fall in love. Mbatha-Raw, transcendently fiery and moving in last year’s Beyond the Lights, gets relegated to the role of the dutiful spouse, present only to look concerned and occasional encourage with trite platitudes (and, perhaps on a more fundamental level, to keep Concussion from being a movie without a single substantial female character). Prema is also the subject of Concussion’s strangest sequence, which implies that a great personal tragedy was indirectly caused by someone (the NFL?) tailing her in her car.

Smith acquits himself well in a tough role; his Nigerian accent is convincing, as are his rare (very rare) scenes of quiet, smoldering intensity. But even with one of our best movie stars at its center, Concussion is more issue than movie. It’s the very definition of a film with its heart in the right place. And also a prime example of how good intentions don’t automatically make great movies.