Drink...
For the first appearance of each main character and say "Welcome to the party!"
When someone dies. Drink twice when a dead character comes back to sing at the end.
When there's a note or letter.
When they get a detail from the book right.
When you can see the conductor. Drink twice if he sings along.
When there's a shot of some of the musicians. Select a particular instrument and drink twice when you see it.
When a title appears. Drink twice if you could read it on the big screens before it appeared at the bottom of the screen.
When there's a wide shot so you can see the whole stage. Drink twice and say something patriotic in French if the tricolor light effect is on.
When the lights flash.
When a balloon pops.
When they fade into another shot of the same person so that for a little bit there are two different shots of the same person on the screen at the same time.
When you can hear someone panting in the microphone.
When the audience claps for a really long time. Drink twice if the audience started to clap before the last note was over, or if the audience is still clapping when the next song starts.
When someone holds out the last note of a song for a really, really long time (the Bishop being Exhibit A--check out the look Colm Wilkinson gives him, like "Good Lord! How long are you going to keep that up?").
If you can figure out which student (excluding Grantaire and Enjolras) is which--without looking at a copy of the libretto, that is.
When someone takes off or puts on a coat. Drink also when you can infer that a character took off or put on a coat, even though it might not be shown on the tape.
When Javert refers to himself in the third person, and mutter about how that sort of thing isn't the sign of a healthy mind.
When Marius is jolly. (Or when Eponine is wistful, or when Valjean is resolute.)
When someone looks more angsty or distressed or worried than usual (what's "usual" is a matter for the viewer's discretion).
When Grantaire sings (just for the principle of the thing).
When Colm Wilkinson ends a high note with a yelp.
When Philip Quast glares at Colm Wilkinson, and say "Has he had all his shots?"
When there's a policeman (including the National Guards at the barricade) on the scene who's NOT Javert and say "About time someone else showed up!"
When someone adjusts a mic.
When a big group of people stands up or sits down.
When Valjean tells Javert to "go," drink if you notice that ironically an EXIT sign is visible in the background and say, "What's the hold up? The way out's right behind you!"
When you notice that for having just sold her hair, Fantine sure does have a lot of it left.
When they show pictures or video footage not from the actual concert. Drink twice if the actors in the video are moving in slow-mo.
When you can see the seated actors talking among themselves, etc.
When the seated actors clap or sway along with the music.
When someone takes a drink from their water bottle.
Finish your drink at the end while the actors smile disconcertingly and bow. Snort your drink with laughter when Colm Wilkinson turns around and hugs Philip Quast.