Marcellus explains the mechanics of his escapes: he threads a tentacle through a gap around the pump housing near the top of his enclosure, unscrews it, and slips through the small opening into the pump room. Once out, he is racing an 18-minute limit before The Consequences of air exposure overwhelm him.

He weighs two routes each time. Staying in the pump room grants quick access to adjacent tanks with lackluster or risky fare, while breaching the door to the hallway and main tank promises better options but costs precious minutes opening and then reopening the heavy door on return.

He once tried to save time by propping the door with a stool, then leisurely raided a bucket of halibut meant for the sharks. On returning, the prop failed inexplicably. As The Consequences set in, his limbs slowed, vision blurred, color drained, and his suckers went numb, turning his crawl back into a desperate attempt to survive.

Marcellus barely made it, reentering the water, restoring the pump, and retreating to his den as strength and color returned with a gut full of halibut. He resolves never to trust a propped door again, admits he has pushed his limits before, and emphasizes that only he knows about the gap—something he intends to keep from Terry.