Forget which of the Pickwick triplets did it — I’d pay good money to see Eugene Levy kill a man. Indeed, this is a theoretical possibility in the fourth season of Only Murders in the Building, which sees the Arconia trio going Hollywood. But as fun as the prospect of a homicidal Levy — or any other big guest stars — might be, Only Murders doing a showbiz season made me wary. The previous Broadway-centric season bordered on unwatchable, so a seeming reprise...