What. What. While he hadn't had any particular expectation of what would follow, Watson was not in the least prepared for this request. He hesitated, watching Holmes undress -- not just in public, but in the open! -- with a certain degree of interest under his astonishment and hesitation.

He glanced towards the village, half-expecting someone to be coming down towards the beach now. There was no one, but that wasn't particularly reassuring.

"Are you quite mad?" Watson hissed under his breath, although what need there was for whispering, he wasn't sure. And yet, despite everything, after a moment's hesitation, he began to undo his buttons, slowly. "If you have an interest in some outdoor exercise, perhaps we ought to find some cover?"