In Wolfgang Petersen’s film The Perfect Storm, the captain of the fishing boat Andrea Gail played by George Clooney turns to his exhausted crew after the sea begins to become rough again from a brief lull and said in despair: “It’s not letting us out.”

Oswald Grübel, chief executive of UBS, might not want to go public, but he must be beginning to wonder when will the storm raging around his bank will peter out.