Did you ever play that game as a child, “The Floor is Lava”? You know the one — where you can’t touch the floor lest it suck you up and you’re dead forever so you have to travel via precariously-placed footsteps on backs of chairs and tops of tables? That’s what the new episode of Doctor Who looks like — only everything is lava and it sucks you up and generally doesn’t look like much fun at all. Damn aliens!

From the trailer for Saturday’s new episode, “Flatline,” Clara and Twelve, it seems, have been separated for reasons we do not yet know. Clara must then tackle these were two-dimensional alien thingies (or whatever the heck they are) all by her lonesome with nothing more than a sonic screwdriver to save her.

The official synopsis for the episode doesn’t give us any further clues, really, either — but for argument’s sake, here it is: Separated from the Doctor, Clara discovers a new menace from another dimension. But how do you hide when even the walls are no protection? With people to save and the Doctor trapped, Clara comes up against an enemy that exists beyond human perception.

Messing with our perception, are you, Doctor? Hmm! It feels as though that is a theme we’ve run up against this entire season. What are you playing at, Moffat? This episode is the second (in a row) to be written by Jamie Mathieson, so no doubt there may be some continuation of the themes from “Mummy on the Orient Express” happening here, too. We’ve clearly got a lot to dissect in these last few episodes of the season — we still don’t know what Missy’s deal is, to say nothing of discussing the Doctor’s face.

Are you looking forward to the new episode? Leave your thoughts in the comments.

Image: BBC