Jeff Wayne released his musical version of The War of the Worlds in 1978, adapting H. G. Wells' 1898 novel about a Martian invasion of England. The Tripods are the Martians' towering war machines, and their chilling cry, written as Ulla in the novel, became one of the story's most recognisable elements. Wayne's dramatic, orchestral take kept that alien call front and centre. Online, the clip has outlived the album as a standalone invasion cue, shared in edits, games and memes whenever something colossal arrives.