They Shoot Gilmores, Don't They? - S3-E7
Corrected entry: This whole episode is based on a 24 hour dance contest. When we see Lorelie and Rory going it is 5:30 in the morning and dark. It stays dark the whole day, and you know this because when Jess and Shayne show up he goes and gets a sandwich which is at noon but it is still dark out. (01:00:00)
Correction: It never says what time it is when they get the sandwiches. It could have been at night.