Several films have been made about Nelson Mandela, the South African politician and Nobel Prize winner, and just about all of them suffer from the same fundamental flaw: The very qualities that make the man such a revered figure—his selfless devotion to change, his unfailing moral rectitude—also make him a pretty dull subject for a movie. Pure nobility just isn’t very dramatic, which is perhaps why no one has ever made a major motion picture about Mother Teresa.

Initially, and in theory, Mandela: Long Walk To Freedom seems to have found a solution to this recurring problem. The film devotes much of its first half to Mandela’s campaign against the South African government in the ’50s, which means viewers get to see him as a young, angry revolutionary, instead of the wise and wizened leader who’d later grace television screens worldwide. What’s more, the future president is portrayed here by Idris Elba (The Wire, Prometheus), whose clenched-fist charisma is a far cry from the paternal saintliness other actors have brought to the role. Elba may not look or sound much like Mandela, but he’s plenty convincing as someone who could inspire a nation—Pacific Rim proved he’s good with public speaking—and even more so as a budding big thinker finding his calling.

Were Mandela solely interested in that early chapter of its subject’s life, when he was reluctantly turning to violent tactics in the war on apartheid, the film might have achieved a uniquely complicated perspective. Alas, the first passage is just a portion of what turns out to be a typically sprawling, bloated biopic—an earnest but misguided attempt to cram a lifetime’s worth of Important Events into two hours and 20 minutes of running time. Though based on Long Walk To Freedom, the politician’s bestselling 1994 autobiography, Mandela often feels more like an adaptation of his Wikipedia page. Director Justin Chadwick (The Other Boleyn Girl) condenses each historical chapter—from Mandela’s salad days as a womanizing freedom fighter, to his decades behind bars, to his unconditional release—into an endless, churning montage. There’s little time to stop and breathe in the moment, because the movie is constantly pushing on to the next bullet point. The passage of time also becomes a blur: Around the midway point, Mandela arrives at Robben Island to serve his life sentence, and though the film briefly, promisingly threatens to become a prison drama, Chadwick covers those 18 years in fast forward. In doing so, he loses the significance of Mandela’s sacrifice; it’s a casualty of the script’s stubborn comprehensiveness.

Mandela has its stirring moments, as just about any version of this triumphant story would. Late in the film, a still-imprisoned Mandela sits down with the white South African leadership to help broker peace, and it’s difficult not to be inspired by his refusal to bend on the matter of equal rights. (He knew that he was on the right side of history and that victory was, at this point, a waiting game.) But the same effect could be achieved by simply reading about those meetings. And when Chadwick and his writers periodically shift to Mandela’s relationship problems with wife Winnie (a fierce, underused Naomie Harris)—who became an activist in her own right and was the subject of her own film earlier this year—it just feels like more biopic boilerplate. Even Elba, who’s strong in the early scenes, can’t rise above the limitations of this genre: The older his Mandela gets, the more he forgoes performance for impersonation, letting the makeup team do the hard work. Offering countless facts but little insight, Mandela fails most crucially at revealing the real man behind the icon. Ultimately, the film needed to either narrow its focus to one aspect of the Mandela narrative (as Clint Eastwood did with the slightly more successful Invictus) or go the Carlos mini-series route and include everything. As is, it plays like empty tribute—a life story with no life to it.