Funny thing is that is exactly what happened to one of my friends years ago! He was flying a 402 back to Kotzebue, AK at night and basically one alternator fried itself and some how took out the other than the battery immediately died. Oh and did I mention his flashlight was in his flight bag stowed in the nose baggage.

He moved over to the right seat because it had a DG and he could just make out the instruments. He than let down over the ocean and was able to make out the lights of Kotzebue.

Last I heard he was flying for Fedex.