You're The Triangle Guy!
About a third of the way into the first episode of Atlantis, I had to pause and fire off a distressed e-mail to th_esaurus — :
ATLANTIS IS MERLIN IN ANCIENT GREECE WITH TIME TRAVEL
(THE MAIN CHARACTER LOSES HIS SHIRT FOUR MINUTES IN, IT IS DEFINITELY MERLIN)
I'M NOT EVEN HALFWAY THROUGH THE FIRST EPISODE
I LOVE IT ALREADY
I'M EVEN 'SHIPPING SOMETHING
THIS IS A DISASTER
Then I finished the episode and spent half an hour looking through Atlantis GIFs on Tumblr and shouting 'NO' at myself.
There's only been one episode, so I suppose things could change, but I can say this much for now: if you liked Merlin, you will probably like Atlantis. If you hated Merlin but nevertheless derived a strange sense of enjoyment from watching it, you will probably hate-love Atlantis as well.
If you haven't watched Merlin and therefore can't use that as a basis, here's a second 'Is Atlantis For Me?' test: if you are looking for high-quality drama, stay away. If you're looking for something ridiculous about a modern-day young man being thrown into Ancient Greece (a turn of events he inexplicably accepts within about five seconds) and developing a gratuitously homoerotic friendship with Pythagoras, I don't know why you're not watching it right now. It's available on BBC iPlayer if you're in the UK.
I think it has very strong potential to be the next big fandom thing.