'Brady Bunch' Cast Reunites at Famous House For Filming With HGTV

It's throwback Thursday at the famous 'Brady Bunch' house, where the main cast from the 1970s sitcom is getting back together to shoot for HGTV's new show about the groovy makeover going down at their old crib.

As you can see in our pics ... Marcia, Greg, Peter and Bobby Brady -- otherwise known as Maureen McCormick, Barry Williams, Christopher Knight and Mike Lookinland -- staged a mini-reunion at the site of the Studio City, CA home used for exteriors on the show.

Greg and Marcia, Marcia, Marcia looked especially close. Oh, and don't worry ... Eve Plumb and Susan Olsen (Jan and Cindy) were also there, but stayed out of view of our camera.

We broke the story ... after scooping up the property in a $3-plus million deal, HGTV plans to blow out the home's interior and backyard to make a replica of the sitcom set. The project will expand the home from 2,400 sq ft to more than 6,000 sq ft.

Obviously, this will also require cheesing up the place, making it 1973 authentic with cottage cheese ceilings and all to duplicate the show.

As we reported, neighbors were PISSED OFF by expansion plans -- but, if you ask us, seeing the Bradys on the block is pretty cool. We suggest the whole Bunch go door-to-door to ease tensions.