Jessica Alba and Jack Black formed an unlikely couple when they appeared in a Super Bowl special episode of The Office.The A-listers starred as themselves in a one-hour special of the US show in a spoof film in which the funnyman falls for Alba's grandmother.

The subplot sees Jim, the sales rep played by John Krasinski, Pam, the receptionist played by Jenna Fischer, and Andy, a salesman played by Ed Helms, watch the duo on a pirate film illegally downloaded off the internet.

Black, 39, plays Alba's boyfriend who is being taken home to meet her grandmother for the first time.But The School Of Rock star, not quite content with the stunning actress, opts for her older relative instead.

Her grandmother, played by 82-year-old Cloris Leachman, develops a crush on Black and the two end up in a compromising situation after he helps her naked out of the bath.

Alba, 27, is spurned in favour of the octogenarian, but ultimately Black has his heart broken when he discovers his elderly lover in a clinch with another toyboy.Black may not have seen the special episode though as he is currently taking time out on a beach break in Mexico with wife Tanya Haden.

The actor is set to star in the new adaptation of Gulliver's Travels, which will start shooting in Britain in March.It will be directed by Rob Letterman, best known for his work on Shrek and Shark, and is based on the classical Jonathan Swift novel. Alba meanwhile is currently shooting An Invisible Sign Of My Own in which she plays a maths genius who withdraws from life after her father falls ill.