Big Plot Cards often crop up in my own work, and in the work of my fellow strugglers. Especially drama. Don't know where your story's going? Play the BPC. Could be anything that lands like a bombshell on your script. Character not working? Make him a terrorist. Story fizzles out? Have the characters all get killed in a freak gas explosion. No matter what the problem with your script, you can fix it with a BPC, except you can't.
It reminds me of when I was a teenager, playing Dungeons and Dragons instead of going to parties where girls were. Whenever the role-playing adventure started to flag, leaving us in danger of remembering what total losers we were in real life, it would fall to the Dungeon Master to bring back the magic that made us forget. So he'd crouch down behind his Dungeon Master's Screen to summon something up. If he was good, he'd come back with just the spark you needed to get your imagination going again, and you'd be once more a seventh level assassin, on a mission of blood. But more often, he'd throw in a big treasure you hadn't earned or a big monster to kill you. Either way, the game was over.
It's the same thing when you get stuck on a story. You can try putting in bigger treasures (a wedding!), overpowered monsters (an evil psychopath!), or stronger magic (incest!), but it won't work. Unless it does, of course.
Oh, and a merry Christmas! If I don't see you.
9 minutes ago