What was Phil Collins meaning behind tonight tonight?

Answer:

Collins wrote this about the anger he felt after divorcing his first wife Andrea in 1979. He was so devastated that he left Genesis for a short time.

The meaning of this song became a pervasive Urban Myth. The story, which is not true, is that Collins watched as a man who raped his wife drowned. Another version has Collins writing this about about a man who watched another drown, and singing it to him at a concert. Yet another variation claims that when Collins was a young boy, he witnessed a man drowning someone but was too far away to help. Later, he hired a private detective to find the man, sent him a free ticket to his concert, and premiered the song that night with the spotlight on the man the whole time. These stories are not true.