vehemently disagree with watching "In the Beginning" before watching season 1 because of the major spoilers with Sinclair.
It doesn't say what's going on, and the story also goes on beyond that before the show is over. It's not a spoiler, it's a tantalizer. I'd only seen a few episodes here and there, but then they put that movie out and started showing it from the beginning on TNT, it really got me into the show. Left a lot of questions but I was anxious to find out the answers by watching every single episode. Whenever I re-watch the series, I always lead off with ITB and TG.
BTW, when the show started, Sinclair made me lose interest, but not quite as much as Londo's hair. Oh boy. LOL
I ended up liking Sinclair/O'Hare a lot more later, but he's certainly no TRON
...er Boxleitner. Bruce was MADE for this role. The show ends up being absolutely epic.