" He gasped and looked over my shoulder. “There he is!” We fell for it. As soon as we turned, Sisyphus took off down the hill. “I’m free! I’m free! I’m—ACK!” Ten feet from the hill, he hit the end of his invisible leash and fell on his back. Nico and I grabbed his arms and hauled him up the hill. “Curse you!” He let loose with bad words in Ancient Greek, Latin, English, French, and several other languages I didn’t recognize. “I’ll never help you! Go to Hades! "
― Rick Riordan , The Demigod Files (Percy Jackson and the Olympians #4.5)