Bryan Cranston. (WENN)

Watch out, Jack Donaghy; Heisenberg’s coming your way, and you know how he deals with rival alpha males.

“Breaking Bad” star Bryan Cranston will guest-star on “30 Rock” this season, along with Catherine O’Hara, NBC told TheWrap. O’Hara and Cranston will play the mother of NBC page-turned-janitor Kenneth Parcell (Jack McBrayer) on an upcoming episode.

“30 Rock” returns for its seventh and final season of 13 episodes Oct. 4.

Cranston recently took part in another NBC sitcom, albeit behind the camera. The actor directed an episode of “The Office” earlier this month. “Free meth for The Office! (look who’s directing...),” “Office” star Rainn Wilson announced via his Twitter account, posting a picture of himself and Cranston on set.

TV Guide first reported the news of Cranston and O’Hara’s “30 Rock” casting.