"Nightfall" by Isaac Asimov (you can hear the story here on escapepod, if you need it) postulates a planet in a multi-sun system. The orbital mechanics of the 6 suns result in all of the sides of the planet being illuminated all of the time but for one short period of a single 'day', at the 5 big suns just happen to align on one side of the planet with the dimmest one blackened out by the single moon opposite to them, leaving it to rotate a full time with a considerable (half) of the planet not illuminated. This event happens all ca. 2050 years, resulting in massive fear of the dark and crumbling society.
Now... How would this Hexa-star system have to be set up, assuming there is no other planet or moon?