'Brothers & Sisters' Goes Back in Time: Scoop On the Big 2-Hour Flashback (VIDEO)

'Brothers & Sisters' is one of those shows that can make you laugh hysterically and cry like a baby in the span of an hour. Judging from what I saw on set while they filmed their big two-hour flashback episode (airs Sun., April 11, 9PM ET on ABC), the Walkers have outdone themselves.

With Ken Olin directing, there was also a hoarde of young guest stars -- including Kay Panabaker (young Kitty), Anna Wood (young Sarah) and Kasey Campbell (young Kevin) -- drinking Tab, flaunting big '80s hair and pressing on their brightly colored nails.

I talked to the show's matriarch Sally Field about doing the flashback thing and learning more about her character, Nora, through this glimpse into her past; and star Matthew Rhys, who plays Kevin, hinted about the family's dark secrets, which we'll see quite a bit of this week.

Then guest star Colin Egglesfield -- who'll play the younger version of Fields' TV husband -- dished about transitioning from '80s to '70s William Walker, working with Sally Field, playing a dad for the first time and the trouble his TV kids get into.

Enjoy our behind the scenes peek ...