Complex sentence: He returns to Venice and sings but a'killer storm' approaches, endangering everyone and even the The Church of Souls of Those Who Die at Sea, which is the most sacred buiding to the Gondoliers.
Split into simpler sentences: He returns to Venice and sings but a'killer storm' approaches. Every one is endangered and even the The Church of Souls of Those Who Die at Sea, which is the most sacred buiding to the Gondoliers.