A decade on, the Oscar-winning portrait of American slavery feels more potent than ever. The filmmakers explain its personal origins and ultimate triumph.“So, what do you want to do next?”The question shadowed the director Steve McQueen’s first tour of Hollywood, in late summer 2008. His debut film, “Hunger,” a mesmerizing and unsettling character study of the Irish revolutionary Bobby Sands, had electrified audiences in Cannes that May and won the prize for best first feature. In rounds of meetings in Los Angeles — McQueen’s first time in the city — executives and producers on studio lots and in restaurants cast themselves as allies-in-waiting, eager to help a visionary new talent mount his second picture.McQueen had thought his follow-up would tackle another formidable historical figure, perhaps the African American singer, actor and activist Paul Robeson, or the Nigerian Afrobeat pioneer and political dissident Fela Kuti. But, emerging from the Hollywood meetings, he told his agent that he wanted to make a film about slavery. The decision, he said in a recent interview, had been inspired in part by the meetings themselves — an ineffable look he’d seen on people’s faces when they’d first laid eyes on him.“They didn’t know that I was Black,” said McQueen, who was born outside London to a Trinidadian mother and a Grenadian father. “I think because I had made a movie like ‘Hunger,’ these white guys didn’t think that they would be meeting with a Black person.”To McQueen, the mistaken assumption about his identity — to say nothing of the carelessness of not having bothered to look him up — was evidence of deep and unexamined prejudice. The legacy of slavery had haunted him since childhood; his mother kept a family tree that traced her ancestors back to Ghana. But, in Britain, his education on the subject had included “Roots” and little else. In America, a country with an ample history of anti-Black violence, he sensed a similar strain of mass amnesia.“There was a certain sense of nonresponsibility, like it was something deep in the past,” he said. “I wanted to hold people to account, to say, ‘Whoa, whoa, whoa, wait a minute — this happened here.’”“12 Years a Slave,” McQueen’s version of a wake-up call, was released 10 years ago this month. Starring Chiwetel Ejiofor, Michael Fassbender and Lupita Nyong’o — in her first feature film role — and written by John Ridley, it was based on the real-life autobiography of Solomon Northup, a free Black man who was kidnapped in 1841, enslaved and later escaped. (In the end, it was McQueen’s third film. “Shame,” a frank portrait of sex addiction, came out in 2011.)Lupita Nyong’o as Patsey, and Chiwetel Ejiofor as Solomon Northup, in “12 Years a Slave.” The film was based on the 1853 memoir of the real-life Northup, a free Black man who was kidnapped, enslaved and later escaped.Jaap Buitendijk/Searchlight Pictures, via River Road EntertainmentA serious, R-rated Black drama with no movie stars in the lead roles that would go on to gross nearly $190 million (most of it abroad) and win three Oscars (including best picture, the first for a film by a Black director), “12 Years” arrived in Hollywood like a U.F.O. landing. Its success paved the way for two other landmarks of Black cinema from the same production company, Plan B — “Selma” (2014) and “Moonlight” (2016) — and dispelled the longstanding myth that “Black films don’t travel,” one year before Disney announced “Black Panther.”The movie’s journey from gut impulse to unstoppable force was possible because of blind faith — that of an in-demand filmmaker impervious to industry dogma, and a coterie of producers who fanned his flame — and the efforts of actors and crafts people who faced the relics of human bondage, an actual lightning strike and the daily broil of New Orleans in July.These are edited excerpts from their stories.STEVE McQUEEN I knew I wanted to make a movie about a free man who got caught up into slavery.DEDE GARDNER, producer We had a subject matter before we had a narrative.JEREMY KLEINER, producer He has a kind of divining rod for taboos and just goes right to them.McQUEEN My wife [the author and filmmaker Bianca Stigter] said, “Why don’t you try to find some material instead of trying to write it?” John Ridley and I did some research and my wife did some research, and she found the book “12 Years a Slave.” When I read it, I said, This is it. This is the piece.GARDNER The urgency of John’s script, and how cinematic it was, was evident. We try to develop a film as far as we can before going to find the financing. Can we get it written? Can we get it cast? The hope is that eventually you cross a line of deniability.McQUEEN I met Brad [Pitt, co-founder of Plan B] and he was very receptive. He didn’t blink.GARDNER He loved the script and wanted to help get it made, which I think we all knew would entail his being in it. [Pitt plays a small but critical role as a Canadian carpenter and opponent of slavery who helps Northup secure his freedom.]Brad Pitt, left, a co-founder of Plan B, the production company behind the film, on set with McQueen. “I met Brad and he was very receptive,” the director said. “He didn’t blink.”Jaap Buitendijk/Searchlight Pictures, via River Road EntertainmentMcQUEEN I had wanted to do a film about Fela with Chiwetel and I had him learning to play the saxophone. I remember calling him and saying, “Actually, I want to do this slavery film instead.” [Imitating Ejiofor] “Man, I’ve been practicing for the last three months!”BRAD WESTON, former president of New Regency, co-financer The script was great and the talent was undeniable.With a budget set at $20 million, financed by River Road, Summit Entertainment and New Regency, “12 Years” began filming in New Orleans on June 27, 2012. Shooting took place on four former plantations outside the city, not far from where the real Solomon Northup had been held captive. On the first day, the temperature hit 108 degrees.SEAN BOBBITT, cinematographer How hot does hot get?McQUEEN Horses were collapsing in the fields next door to us.ADAM STOCKHAUSEN, production designer It was a battle between wanting to take off as much clothing as possible and not wanting to be eaten alive by mosquitoes.McQUEEN It was brutal, but you realize how people had to live in those conditions.BOBBITT It was very important to Steve that it look real and that it be real. We talked a lot about simplicity and truth, about not having any frippery. The book is very straightforward and honest.STOCKHAUSEN There were terrible storms. One of our sets in the wharf [where a ship carrying Northup arrives in New Orleans] blew down two weeks before we were set to shoot.BOBBITT There was one day when a lightning bolt struck the edge of the ship set and blew out all of our electronics and sound. Everyone — maybe 100 extras and the key actors — hit the ground, screamed and ran away. Luckily, no one was injured, but the E.M.T.s rushed in and checked everyone out.Among the most challenging shoots was a much-discussed scene in which Patsey, an enslaved woman played by Nyong’o, is whipped by the volatile plantation owner Edwin Epps (Fassbender). It unfolds in a single, swirling four-minute shot.BOBBITT It was three or four takes, with one camera. We never used the word “coverage.” It’s anathema to filmmaking — anyone can go out and do 20 shots on each scene, give it to a very good editor, and you’ll get a movie. Will you get a great movie? From my point of view, it’s unlikely.A serious, R-rated Black drama with no movie stars in the lead roles, “12 Years” grossed nearly $190 million and won three Oscars, including best picture.Searchlight Pictures, via River Road EntertainmentMcQUEEN We did a lot of rehearsal and [Nyong’o, Ejiofor and Fassbender] were incredible. Lupita made everyone raise their game. You could put her in a dustbin bag and she would work it out. [Representatives for the actors declined to make them available for this story because of restrictions around interviews during the actors’ strike.]BOBBITT It was emotionally draining for everyone, but the idea was not to give the audience the chance to look away, to drive home the true horror of what was perpetrated on the slaves for 200 years.McQUEEN We couldn’t shy away from it, we had to go to very dark places. But in the evenings, we would all come together, we would hug each other, we would eat together, we would get drunk together, and then we would come back the next day. It was beautiful.The film had its world premiere at the Telluride Film Festival on Aug. 30, 2013. It received a rapturous standing ovation and was instantly hailed as an Oscar contender. But an obstacle came into focus a week later, during a news conference at the Toronto International Film Festival, when a white, visibly uncomfortable moderator repeatedly emphasized how “harrowing,” “brutal” and “tricky” it was.McQUEEN We had a little bit of a … not very good press conference in Toronto. I thought the questions were a bit silly. My response wasn’t great.PAULA WOODS, McQueen’s publicist He was a bit taken aback after having such a great premiere. It fed into this whole “Is it too difficult to watch?” conversation that we were all annoyed by.HANS ZIMMER, composer It was full of injustice, but it was full of human dignity, as well.McQUEEN Cameron Bailey [then the artistic director of the Toronto festival] took me to one side and said, “You know, this movie’s more important than you.” I had to put my emotions aside and get on with the job of promoting the movie.WOODS Before #OscarsSoWhite, people would write things that would never get written today. It’s part of the greater problem of systemic racism. I remember we were in New Orleans visiting one of the plantations with a journalist, and a man who was working there sidled up to me — with one eye on Steve — and said, “You know, it wasn’t nearly as bad as they say it was.”“It was emotionally draining for everyone,” said Sean Bobbitt, the cinematographer, “but the idea was not to give the audience the chance to look away.”Jaap Buitendijk/Searchlight Pictures, via River Road EntertainmentNANCY UTLEY, former co-chairman of the distributor Fox Searchlight It was challenging, but that’s part of what we thought made it special — that it was willing to take you places that are difficult to go.STEVE GILULA, former co-chairman of Fox Searchlight We had a two-pronged approach with the campaign: One was the festivals, and the other was African American opinion makers.UTLEY We did screenings with Skip [Henry Louis] Gates Jr., the Equal Justice Initiative, the National Association of Black Journalists, the Museum of Tolerance.GILULA We didn’t want it to be pigeonholed as an art film. When we opened, it performed very well at African American theaters.After winning top prizes at the Golden Globes and the BAFTAs, “12 Years a Slave” entered Oscar night, on March 2, 2014, with nine nominations, close behind Alfonso Cuarón’s “Gravity” and David O. Russell’s “American Hustle,” with 10 each. The best picture race was widely considered a tossup.McQUEEN I came with my mother and sister, and when we got out on the red carpet they just burst into tears.WESTON We knew that we were in the conversation in a real way, but you don’t let yourself go further than that. You never know.KLEINER There’s an old mythology that films that are a little tougher might not be to the academy’s taste. “Ordinary People” over “Raging Bull.”Nyong’o and Ridley were early winners in the best supporting actress and best adapted screenplay categories. But, late in the night, best director went to Cuarón.UTLEY That’s when your heart goes in your stomach, because often director and picture are paired.McQUEEN Will Smith [presenting best picture] looked directly at me and said, “12 Years a Slave.” It was amazing. I slapped it out of the presenter’s hand, gave my speech and jumped as high as I could.UTLEY It was a calling card for a lot of the talent in the movie, and for us, as well. Everyone got to make more stuff.KLEINER It felt significant that when people now think about how this industry has represented that period — “Birth of a Nation,” “Gone With the Wind” — they might also think of “12 Years a Slave.”BOBBITT There are states in America where that film would be banned from schools today, but it’s there, and it will always be there.McQUEEN We made history. At that point, there was no going back. More