Julie Carmen, Sheila Kelley, Fran Kranz, Judith Light, Julio Oscar Mechoso and Mary Kay Place are joining Patricia Clarkson in indie comedy “Last Weekend.”Pic is in production in the Lake Tahoe area with Tom Dolby and Tom Williams making their directorial debut. Dolby penned the script. Mike S. Ryan (“Junebug”) is producing with Mark Johnson exec producing. “Last Weekend” takes place over a four-day summer holiday at a Northern California estate overlooking Lake Tahoe, where their two sons and assorted friends and partners have been invited for a long weekend. Leisure gives way to chaos as a series of events disturbs the carefully planned festivities. Kranz stars as one of the weekend guests. Carmen and Mechoso portray the house staff; Place and Kelley play family friends and Light plays the flamboyant neighbor. Previously announced cast include Zachary Booth, Joseph Cross, Devon Graye, Jayma Mays, Chris Mulkey, Alexia Rasmussen and Rutina Wesley.