Photo Illustration by Thomas Levinson/The Daily Beast/Getty/HuluFew shows bring a smile to one’s face as consistently as Only Murders in the Building, and Steve Martin and John Hoffman’s half-hour murder-mystery comedy continues to succeed in that regard with its third season, which premieres on Aug. 8. Adding Meryl Streep and Paul Rudd to its cast, the Hulu hit once again weaves a tangled web of homicidal intrigue, and its characters and routine are now so well established that it can assuredly