Not one of Ken Loach's best, though it is moving and well acted. It's about a former mining village in the north-east where everything is closed down and the local pub - the eponymous Old Oak - is just about holding on. A group of Syrian refugees are housed in the village, where house prices are in free fall, and where the locals who already feel dumped on feel that these people are just one more thing that's been dumped on them. The pub landlord tries to be kind and welcoming, but his remaining regulars are hostile and racist.
A good scenario, and lots of sensitive and thoughtful portrayal of the locals...the Syrians are more like ciphers, apart from the female lead played by Ebla Mari, who is a photographer and a rounded-out character. Incidentally, I note in passing the actor is actually a Druze woman from the Golan Heights, so she's never lived in Syria, having been born and grown up under Israeli occupation; oddly this may have kept her alive, because ISIS massacred Druze in the civil war.
The film is pretty bleak, but then ends with an entirely implausible happy ending in which one of the Syrian families hears that their father, who was missing and then briefly believed to have been found, has died. The entire community, including some of the horrible racists, rallies round to support them in their mourning. The final scene shows the refugees accepted into the traditions of the local labour movement and marching with their own Arabic-inflected banner in the Durham Miners' Gala.