When I was younger, I worked for a DoD company that was on a very tight schedule for a single project. Management decided we need to go to 24/7(which was the right decision), but they didn't want to commit a single group to the night shift. They split us all into three groups and rotated us every two weeks. First to Second to Third to First...etc
When I was on Third, I'd get off work around 8am, so it was rush hour traffic in the Twin Cities. I was so tired I couldn't keep an eye on all of the traffic. I would get on the Interstate and just focus on the rear license plate in front of me. I could see, peripherally, as my exit came up, so I'd move onto that and then grab a hold of the first car in front of me. I'd do that until I got home. And then I'd have to try to sleep during the day. Not a fun 4 months or so.