A black cat is rescued from ruffians and brought to Sherlock Holmes. Sarah Bernhardt comes to Holmes regarding missing jewels and takes the cat home with her naming him Midnight. The cat does some investigating and leaves a clue for Holmes, who then solves the case. Midnight then leaves Bernhardt and hits the streets where Irene Adler and Penelope Huxleigh find him and take him home, naming him Midnight Louie.