We are diving into unknown waters this week as we plunge deeply into the depths. (Just as I'm plunging into puns... I'll stop now) This week is the penultimate of the 1x image Categories that we have been exploring and hence nearly the last Pick of The Week. I hope you have enjoyed the journey.

The photographer Petr Polach  has captured that very otherworldly sense of life that is found underwater. His extraordinary image shows us beautifully this transformed and alien world, where we are the aliens and where we must tread (swim) carefully, if we are to survive the experience. I've done a little scuba, but diving in caves must be on another level of difficulty. Even ordinary diving is a risky sport, and here I'm going to give a shameless plug to my own experiences in this regard, which you can read in this magazine via this link. 

Many congratulations to Petr, both for exploring this dangerously lovely place and for capturing and sharing this great shot!