The episode, which is entitled "An Ideal Husband," will also feature guest star Jeremy Davidson.
"Everyone in the Walker family is willing to forgive and forget Scotty's infidelity," according to press notes. "But when the family all put their best foot forward to help them reunite, things end up in a fist fight. Meanwhile Jack is reinvigorated by being back in the city and starts to pursue new ventures, but Kitty can't seem to picture herself in this new life, and Sarah and Luc share some exciting news with the family."
"Brothers & Sisters" stars Dave Annable as Justin Walker, Sally Field as Nora Holden, Calista Flockhart as Kitty Walker, Rachel Griffiths as Sarah Walker, Luke Macfarlane as Scotty Wandell, Gilles Marini as Luc Laurent, Matthew Rhys as Kevin Walker, Ron Rifkin as Saul Holden and Patricia Wettig as Holly Harper.
"An Ideal Husband" was written by David Marshall Grant and Michael J. Cinquemani and directed by Bethany Rooney.
"Brothers and Sisters" airs Sundays at 10 PM ET on ABC.
Hanke, who was seen in the Public Theater's presentation of Hair at the Delacorte, has appeared in the Broadway musicals Cry-Baby, Rent and In My Life. His national touring credits include Big River, The Full Monty and Fame. Hanke has been seen on screen in "Clear Blue Tuesday," "Killing the Badge," "A Children's Miracle," "Marsh" and "Sam Sung."