My Son was built solely on the gimmick that James McAvoy was not given a script. Every line of dialogue from him was improvised, with the actor and audience discovering the truth of the film simultaneously. The problem with this idea is that there's no gradual build-up. No hints, no narrative structure. Shit just happens, and McAvoy reacts to it. It holds the film back tremendously, and despite McAvoy's performance, there's barely a coherent film containing it. And that's a damn shame, because it's a brilliant concept that could do wonders in the right hands.
McAvoy is Edmond Murray, an oil executive (which is mentioned many times in the first half, but turns out to be meaningless) who learns from his ex-wife Joan (Foy) that their son is missing. The police are leaning towards kidnapping, but there's been no ransom demands. When the higher ups insist the case be abandoned (another seemingly important thread that's never picked up again), Edmond is on his own. He discovers his son has been kidnapped by a human trafficking ring, and then the film just sort of stops. The ending is so out of the blue and abrupt that I thought my TV had stopped working.
My Son has all the makings of a great mystery, but it relies too much on the improvisation gimmick. And it's not even that amazing. McAvoy isn't improvising monologues or anything of substance. It's mostly just answering questions with yes or no answers and crying at videos of his son. An actor of his caliber deserves better than this, and now I fear Peacock may be going down the Paramount Plus route in regards to low quality film output.