While Stiles had prepared for something like this to happen, he didn't actually think it would. He hadn't realized the call would work so strongly on him.

He gasps as he's pulled under, and the last thing he sees before the darkness of the ocean takes over is Peter's surprises face. He can't see much in the murky depths, but he can feel the sharp claws dragging him deeper- and Peter's strong hold trying to pull him back to the surface.

With his free hand, Stiles wrenches the other iron knife he'd enchanted from his pants pocket and slashes wildly at the clawed hands gripping him. He hears a faint pained screech and the weight dragging him down and suddenly lifted, allowing Peter to pull him up.