Almost at the end of a lesser season of episodes from Black Mirror, Metalhead is probably one of the stronger episodes. The 40 minutes is stripped down to base elements. It is in black/white, only has a handful of characters, and is basically one extended chase sequence. Set in a post-apocalyptic world, a small group of survivors seek out a package in a warehouse, only to disturb a 'dog' - one of the robot drones that we assume has led to the slaughter of most of mankind. From here the drone hunts down the only character to make it far enough to be considered a chase. In essence it is The Terminator but without any plot or backstory to slow it down.
As such it delivers quite a thrilling and tight episode. Technology is in there, with examples of sleep functions, adaptable apps etc, but it is not really making a point on any of these so much as it is just grounding the episode in the recognizable. In the same way the warehouse could be taken to be an extension of the warehouses today where drone pickers are already starting to be used - but again it doesn't labor this point. The stripped down basic essence of it works well, and the special effects are effective - I assume a mix of physical work and CGI in some way. The ending is perhaps a bit corny but brings in a bit of humanity into what is otherwise a technological horror.
Not the best the series has to offer, but an strong episode in the season and effective at what it does.