Dirty secret

A turtle in his tank, is rather tired and dull. His master lifts him up, quite a long way to fall. They exchange a brief glance, and master turns his head. His picks up the turtle's rock by chance, and his face displays brief dread. Eyebrows raised in happy surprise, master looks into his turtle's eyes. For under the rock were no coins nor bucks, but an orange mask and pair of nunchucks.