30 Rock Season 5 Episode 6 (30 Rock s05e06) with title “Gentleman’s Intermission” aired on Thursday, November 4th 2010 08:30 pm at via NBC Network.
Here is summary for 30 Rock Season 5 Episode 6 :

When Avery points out the peculiarity of Jack and Liz’s bond, he vows to set some boundaries. With Jack keeping his distance, Liz is left to deal with her father’s attempt to recapture his youth during a visit.