O'Toole will reprise her role as Martha Kent, Clark's adoptive mother, and McKean will return as journalist Perry White.
White, who becomes Clark Kent's editor at The Daily Planet in the comic book mythology, will have a first meeting with Lois Lane in the series, according to EW.com, and Ma Kent (who became a U.S. senator and left the series a couple seasons ago) will return with a surprise or two. O'Toole and McKean have been married since 1999.
O'Toole has appeared on screen in "Smile," "Vanities" and "Superman III," and Off-Broadway in The Seagull and Kindness Off-Broadway. McKean starred as Lenny on the hit television show "Laverne & Shirley," and on Broadway as Edna in Hairspray, Hines in The Pajama Game and most recently, as Arthur in Superior Donuts.
The ninth season of "Smallville" began in September and McKean and O'Toole will appear together in episode 21.
— Allison Klamkin