Even at its guest-starringest, "Will & Grace" had nothing on "The Odd Couple"’s fourth season stunt casting. Just two months after their epic "Battle of the Sexes" drew the largest-ever live audience for a tennis match, Bobby Riggs and Billie Jean King squared off against each other at the ping-pong table in the episode, "The Pig Who Came to Dinner." Ballet superstar Edward Villella performs in "Last Tango in Newark" and Marilyn Horn, as a baker with an operatic voice and an unrequited crush on Oscar, sings selections from "Carmen", as well as "People," in "Vocal Girl Makes Good." "The Songwriter" features legendary disc jockey Wolfman Jack and entertainer Jaye P. Morgan, who performs the ever-popular Felix-penned ditty, "Happy and Peppy and Bursting with Love." "Playboy" emperor Hugh Hefner drops in for the flashback episode, "One for the Bunny," in which a jealous Felix is undone when he must photograph his future wife, Gloria, for a possible Playmate spread. But the chemistry between Tony Randall and Jack Klugman, Best Actor Emmy nominees in each of this series’ five years, is the real attraction. They are so thoroughly at home in their roles that they elevate the more over-the-top material, as witness their ill-fated presentation as glue entrepreneurs in "A Barnacle Adventure." Among the season’s best episodes are the ones that go back to the basics of Neil Simon’s warhorse play: Can two divorced men share an apartment without driving each other crazy? In "The Insomniac," Felix cannot get to sleep ("I’m up as a pup") despite Oscar’s best efforts. In "Cleanliness is Next to Impossible," Felix hypnotizes the unwitting Oscar into becoming a neat freak after Oscar’s new girlfriend calls him sloppy (Felix’s heartbreak at having to bring Oscar out of it is palpable. "It’s like a dream come true," he moans). Elinor Donahue’s Miriam, Felix’s girlfriend, is conveniently forgotten in the episodes in which Felix tries to win back his ex-wife ("Gloria Moves In"). Zinger-queen Brett Somers also returns as Oscar’s ex-wife, Blanche, in flashback episodes that continue to play havoc with Felix and Oscar’s backstory (so now they were in the Army together?) Randall, Klugman and company (including Penny Marshall as Oscar’s secretary, Myrna) clearly relish playing to their enthusiastic live audience, and this richly entertaining season is brimming with classic moments and bits of comic business that continue to bring down the house. "--Donald Liebenson"