Stay On the Bus

After Judy decides she doesn't want to get her braces removed and gets on a bus that's full of Judy's teeth, they happily sing to Judy about staying on the bus so she doesn't lose them. But when Judy wants to get off when the bus passes by things she's interested in, she tries to stop the bus but accidentally drives it off a bridge and into water where her teeth tries to drag her down with them as the bus sinks.

Example of:
Descent into Darkness Song