The finale of Only Murders in the Building’s fourth season dropped some jaw-dropping secrets and unexpected turns. Our trio – Charles, Mabel, and Oliver – ultimately discovered who killed Sazz Pataki. It turned out to be Marshall P. Pope, who had been concealing his true self as Rex Bailey, a former stuntman and an old friend of Sazz. Envious of Sazz’s skill and writing success, Rex swiped her script and pretended to be the author under the pseudonym ‘Marshall,’ hoping to boost his career by riding on her fame. Once Sazz learned about his deception, she threatened to expose him. Fearing his secret would be revealed, Rex orchestrated and carried out Sazz’s murder to safeguard his deceit.