"I was just throwing them," Scully admits, perhaps a little defensively, and hefts the pebble in her hand. "They're too round to skip."

She probably can find one the right shape to skip, if she tries, but does that even work over breakers?

Some things come back to her, she's found. Nothing personal, but little details: what pyrokinesis is, how to swim, which foods on the buffet are most likely to give them all food poisoning after sitting out in the bright beach sun for hours. Rock skipping on the ocean is drawing a blank.