Complex sentence: Mr. Wick decides to leave Mrs. Louder's prize breeding dog Lucky with Kate, who then takes him to Drew's house he gets there, he's not in, so she decides to leave him there with a note.
Split into simpler sentences: Mr. Wick decides to leave Mrs. Louder's prize breeding dog Lucky with Kate, who then takes him to Drew's house. When she gets there, Drew's not in, so she decides to leave the dog there with a note.