Complex sentence: The smash hit "Billy Don't Be A Hero" stayed three weeks at No.1 on the British Chart in March 1974, and an equally catchy story song reached the No.3 position; it was called "The Night Chicago Died".
Split into simpler sentences: The smash hit "Billy Don't Be A Hero" stayed three weeks at Number one on the UK Singles Chart in March 1974. It was followed by an equally catchy story song, which reached the Number 3 called "The Night Chicago Died".