Leonard Snart is a real up and comer in the crime world. He’s ruthless, clever, and doesn’t care who he has to screw over to get what he wants. That is, until he screws over the Santini family. No one screws over Vincent Santini and gets away with it, and Len is no exception. That’s how he ends up with weights chained to his legs, sinking to the bottom of the river.
He knows he’s going to die. He knows that he’s going to drown, that his sister will never know what happened to him. As he passes out, though, a beautiful face appears in front of him. When he wakes up, he’s on the river bank, safe and not dead. The face haunts his dreams, whispers of a song and the cold press of lips against his bouncing around in his brain.
Then, Barry Allen walks on shore.
Barry comes from a race of killers. The laws of the merpeople say that any people they come across are to be drowned. But Barry is not a killer. So, when he sees a human trapped and drowning, he doesn’t even think about leaving him. He gives him a kiss, which grants humans the ability to breathe underwater, and carries the human to shore.
Barry can’t get the man out of his head, though. So, he does what he was already warned not to. Barry steps out of the water, granting him legs for until the next full moon. By the ancient laws, if Barry is granted a vow of love by the one he kissed, he will be able to keep his legs. If not, he will be put to death once he returns to the water.