The Galapagos sharks. 
Called in by the sound of motor boars, reminding them of fishermen, who fish for crabs and often throw the fish that gets stuck in the nets back into the ocean, providing them with a lovely dinner and making them return over and over again.
On this dive, we got to see two females and one male, somewhat curious.
They watch you from a distance and come closer and try to get to know you. Slowly and gradually they get used to you and let you swim closer, yet they are afraid of bigger groups of people simultaneously in the water.