Submerged

Happened on April 6th, 2014:
I was watching an episode of Doctor Who. I'm not a big fan of this, and I can only watch it on BBC Entertainment. If I want to watch it in Portuguese, then I have to pay to watch Syfy HD, which is part of a package that includes a few boring channels.
The episode's contents were very strang: no Daleks, no TARDIS, no nothing. Just a man swimming on a submerged landscape with sone school lockers. The episode had some great reviews, and they said that they were going to make a month full of this kind of episodes.
Did the main character become a merman? No.