"Wait," Louisa said, reaching to hold her younger brother back from the shore.

"Why?" Simon asked, though he paused behind his sister's gentle restraint.

"The Sea Ladies haven't finished." Louisa pointed to the black-clad figures moving slowly along the strandline. "Only when they're gone can we see what the tide brought in."

"They don't take the shells?" Simon asked, and Louisa shook her head.

"No, they leave the shells and the smooth glass and the lost toys.

"They only take those that sea took. And then they return them."