And Then There Were 7 - S1-E11
Plot hole: When Scofield comes back after visiting his wife, Fernando announces his arrival. However the problem is, everyone is inside digging the hole. As Fernando walks in along with Scofield, it leaves no one outside watching for guards. The guys are at least smart enough to keep the watch outside instead of all staying inside. If a guard shows up unnoticed, they are screwed. (00:09:40)
Answer: Don Self actually worked with Whistler before he died. And Whistler with the bird book actually knew where Scylla was.