Leah imprints on a stranger.

Skye turned to Ward, "That was Agent Lewis? So not what I was expecting," Skye shook her head. "Which was what?" "Middle aged, a bit overweight, grumpy, and-" Skye gestured to the grey walls and suits- "matching." Ward discovers something about Coulson's private life he would rather have remained a secret.

It wasn't possible. On second thought, Steve had seen much weirder stuff then mermaids, so he really shouldn't be freaking out at the idea of a half-fish half-human creature. (The one where Darcy's a mermaid)