They tag along and get their gear out, start the dive, find the house - but also much more than they bargained for, which is where the 'horror' bit comes in with spooks aplenty. Say no more! The two leads' characters are really annoying, maybe purposefully, she an irritating whinger with no spunk that you'd expect from someone trained to deal with tricky underwater situations - and he, cocky overconfident, teaser and bore - the kind of bloke you'd avoid at a party.
Anyway, it's an interesting enough yarn - you'll see the plotline coming from way off of course and be annoyed that if you're in it for the spooks and horror, you'll probably be disappointed as most of it, well, just doesn't really work underwater. The chaos of bubbles and movement every time something looks like being scary kills it dead.
It's OK though - there's a dollop of tension thrown in here and there. A very simple and straightforward short film which amuses for a while! I didn't know anyone in it (though the two leads Camille Rowe and James Jagger seem to have a number of previous appearances elsewhere), nor any of the direction or production team. The creators Alexandre Bustillo and Julien Maury seem to have done a number of similar things in France.