"Playtest" shows a terrifying vision which could actually be a reality in the future. At its core, it's just a man walking around a house screaming a lot. But despite its deceptive simplicity, it becomes a lot more than that due to some disturbing twists.
The episode clearly appeals to gamers, apart from the video game theme there are some blink-and-you'll-miss-it moments (I saw Dark Souls 3 in Sonja's game collection). Although non-gamers will understand the terrifying concept, it would resonate more with gamers, especially those who have tried horror games with VR headsets. It touches on why people play horror games at all when they are, as the name hints, horrible, but the main point of the episode is to show how far VR could go. The twist in this episode is that Cooper has technology inserted into his brain to make him see things are aren't really there. This allows the technology to play with his mind and his senses.
Much of this episode is made up of Cooper walking around the house and while it is tense, and while the sole protagonist's acting is very good and while there is a tone of dark humour, the plot at first is simplistic and predictable.
The real twists come one-by-one near the end of the episode and the final twist changes everything, completely turning what you thought you understood was happening upside down. Brilliant, intense and a shocking ending.