Corrected entry: Whilst Mr Pirelli is in Sweeney Todd's barber shop, Sweeney Todd is seen to be boiling a kettle full of water, however, whilst beating Mr Pirelli half to death no water leaves the kettle or splashes around at all, upon dropping the kettle water floods out of the kettle.
Twotall
17th Jan 2009
Correction: We don't know if the kettle as full to begin with. If Sweeney was only making tea for himself, filling the kettle with more water than needed would just be a waste of time. So if the kettle was say, half-full, then it makes perfect sense that no water sloshes out while it is being swung around (momentum would keep the water in).
Twotall