Complex sentence: Christie's second novel, "The Secret Adversary" (1922), featured new protagonists in the form of detective couple Tommy and Tuppence; again published by The Bodley Head, it earned her £50.
Split into simpler sentences: Christie's second novel, "The Secret Adversary" (1922), featured new detective couple Tommy and Tuppence. Again published by The Bodley Head, it earned her £50.