Yesterday Island - S1.E6

Having ran out of fuel while at sea, the children are given no choice but to moor their boat on the nearest possible island. Whilst there, they discover a museum dedicated to preserving parts of the time before the floods, looked after by a strange middle-aged woman with a literal 'eye socket' named Polly Phemus. Upon trying out her old virtual reality video games, it becomes clear she is trying to trap them, and the group strive to break out of the virtual world and get back to real life.