Alex Thompson’s review published on Letterboxd:
This film told by nearly any other director would not be as successful. Steve McQueen brings his aesthetic wonder to the proceedings marvelously, with at least 3 sustained long takes that are not only impressive technically but also emotionally. But then there's a sequence in which Solomon Northup is nearly hanged and must keep his toes squirming around in the mud to keep his windpipe open which begins with a long-ish take and then cuts to several different angles, each perceptively later in the day to show both the passage of time and the way in which people react (or don't) to his situation. 12 Years a Slave isn't a subtle movie but it doesn't beat you over the head with its ideas or themes. It just tells Northup's story with a steady hand and a keen eye for suffering. It is multifaceted in its characterization, not all the white people are evil nor all the black people (the protagonist included) saintly. The script plays a role there, obviously, but the acting by everybody in the large cast is probably the biggest bearer of this weight. I've always liked Chiwetel Ejiofor and he's great here (just wait for the scene where he sings, it's astounding), Lupita Nyong'o is superb as the target of the reprehensible Michael Fassbender's insidious affections, and so on and so forth.
The impassive, watcher status of Solomon throughout the film really worked for me, especially as it highlights the moments when he does interact with those around him. This is most powerfully demonstrated in the scene/shot which shows Solomon singing. He's buried a slave who died suddenly in a field then a group surrounds him to grieve and sing Roll Jordan Roll. He stands stoically for a while, refusing to get involved more than he must and give into his status as a slave. Then the immense sadness of the situation and his own circumstance overtakes him and he begins to sing along, slowly and quietly. He builds and builds line by line, all the while showing more emotion than he has since getting duped into his situation. McQueen stays close and refuses to cut while all of this happens and it's the saddest thing.