TNG:
Data's Day, The Wounded. Both very good episodes, even if it doesn't make any sense to lower the lights on the bridge for the night shift, given that Data's not the only one there. An android wouldn't care, but humanoids would. I'm just wondering why Deanna didn't realize Ambassador T'Pel wasn't who she claimed she was... Great to see Marc Alaimo as Gul Macet, too.