brimstone: an old name for sulfur
sulfur: an abundant tasteless odorless multivalent nonmetallic element; best known in yellow crystals; occurs in many sulphide and sulphate minerals and even in native form (especially in volcanic regions)
lip synchronization: combining audio and video recording in such a way that the sound is perfectly synchronized with the action that produced it; especially synchronizing the movements of a speaker's lips with the sound of his speech