It happend on a diving trip I made with my girlfriend two years ago in the Gulf of Siam (Thailand).
On this particular morning we left the bay on a cutter with some friends and bottles for three dives, heading twords Chumporn Pinnacle.
Up to this day all members of this voyage had already been diving together for over three weeks, so the climate was pretty relaxed and everybody was simply enjoying themselves. Once we arrived at our destination point the whole pack geared up and got into the water discussing the following dive.
I was the last one to get in and simply didn´t take part in the safety check - instead of this I was busy with my mask cleaning it. I finally put it on beyond surface and you won´t believe what I saw there - instead of the expected deep blue I saw a dotted pattern, which passed my fins 2 m deeper.

IT WAS HUGE.

In this moment I simply couldn´t see how big it really was, but in the same time I knew we were not in danger - it was a whale shark we were paying a visit to and who quickly disappeared in the blue of the indian ocean.
I had to tell the others, who were still busy with their procedure - and first they didn´t want to believe me - but as I finnaly menaced to begin the dive on my own, someone took a look beyond surface and saw the last bit of the shark´s fin.
In this moment the whole diving plan collapsed and the team spontaneusly started the most chaotic and euphoric dive of their lives - everybody tried to reach the shark.
And in fact the shark didn´t leave those grounds yet - he circeld around the pinnacle to get his plancton breakfast.

But he took a break as he saw us, yes I had the impression that he enjoyed our presence just as we enjoyed him - he even stopped changing his deapth and he adjusted his speed to ours - this gave us the opportunity to gain on and follow him.
As all of us were following the shark deeper and deeper into the blue my girlfriend stopped and watched us enjoying the moment and the weightlessness that you can feel as a diver.
In a distance of 30 meters away from her, the fish turned around and came back.
He swam straight towards Tina opening and closing his jaws, which are big enough to hold a middle-class car. At first she wanted to swim away, but she was paralized staring at him.
As teh fish nearly reached her - he was moving quite slowly - he turned off and passed my love in a distance of about 1 meter nearly touching her mask with his huge tailfin.
For a few seconds it was like both, Tina and the fish, were alone down there she later told me.
As I reached him I spend 10 minutes behind his tailfin, which was 2,5 m high - he moved it very slowly, so I stretched out my arm and the fin straved my fingers - oh my god, this was a real miracle!
But I still wasn´t sure about his lenght, so I came to the decision to swim along his side with a distance of 1m! During this maneuver I saw, caused by the restricted view of my mask, just his pattern. The fish was over 10 m long.
So as I finally reached his head, I took a deep look into his eye, which is, comparing to the rest of the body, small.
I realized that the fish was focusing me - and in this second I had not only contact with this living being, but also a view on the sense of life - I can´t explain it better, it was like a drug trip, which changed my life and certainly my point of view according to life.
In this moment of illumination something very funny happend - the fish blinked his eye as he wanted to tell me: \"Hey, take it easy!\"
And I took it easy - the smile I brought home didn´t leave my face for over 3 weeks, but the mood is still here!