So I'm cruising along just NW of Brest and my sonar guy calls out a contact. Warships to the port side, closing at medium speed. Since I'm sleepy I decide to wait till they are in visual range before doing anything. It's night, big waves, a little foggy. I feel safe. I procede at 64x TC.
I keep checking with my hydrophone operator every 5 minutes or so tracking their direction, wishing I could go back to sleep. 280... 260... 250... falling behind to port I assume. The next time I ask for a report, no sound contact. Ok, but just to be sure I ask for any warship contacts. Nothing. Still trying to get some sleep, but I call up to the bridge and ask the WO if there's any visual contacts. He says no.
Fairly confident that danger has passed I climb the ladder to the bridge. By this time I've dropped to 32x TC while I climbed and to enjoy the view without twitching, I drop to 1x as I go through the hatch.
Suddenly SCREAMING! Damage reports coming from everywhere, batteries down, flak down, engines hit, flooding and more flooding! I wildly spin around to see what's happening and there were THREE destroyers just port and aft of us at 1km if that SHOOTING US! Tracers whizzing by and into us! I smack the WO in the back of the head as I dive for the hatch screaming CRASH DIVE!! For some magical reason we plummet to 70m in a matter of seconds, safe.

A few off target depth charge raids later and the destroyers move off.
I REALLY wish I could trust my officers to do things like say "Oh, hey, 1000m over there are three angry destroyers" or my hydrophones to not stop hearing three angry destroyers over there. Ahh well, I lived and only have 51% damage to my hull.