to leave, before going to work. Later, after arriving at work, Liz answers Jenna Maroney's (Jane Krakowski) cellphone, and is surprised to find that Dennis is calling Jenna. Liz pretends to be Jenna and discovers that Jenna and Dennis slept together. Liz is determined not to let this revelation affect her friendship with Jenna, so the two go to confront Dennis about his behavior. During the confrontation, Liz discovers that Jenna and Dennis actually slept together in her bed, leading her to resent Jenna's actions. As a result, she fails to tell Jenna about an improperly attached piece of equipment, leading Jenna to injure her leg. Meanwhile, Jack's fiftieth birthday is approaching and he has received home movies of some of his earlier birthdays from his mother, Collen Donaghy (Elaine Stritch). While watching the tapes, Jack discovers just how happy he was when he was younger, and is determined to reclaim that happiness and innocence. After examining a list he made while he was younger, he discovers that he has done all of the things but one, befriending Batman. Thus, he arranges for actor Adam West, who played Batman, to come to his birthday party. At the party, however, West calls Jack by the wrong name, leading him to realize that he is in fact unhappy, despite his accomplishments. In an effort to reclaim his happiness, Jack attempts to find the same toy that made him so happy on his tenth birthday, a model of an Apollo Lunar Module. He buys one from a vintage toy store, but still remains unhappy. Later, Liz apologizes to Jenna for allowing her to be injured, and agrees to let Jenna tell the TGS writing staff about her role in an advertisement for a phone sex line. The writers find the ad online, and greatly enjoy watching it. Jack comes in while the writers are watching and laughs so hard that he vomits. The laughter lifts Jack out of his bad mood, and he tells Liz what an important friend she is. Production "Apollo, Apollo" was written by executive producer Robert Carlock, making it his eleventh writing credit after "Jack the Writer", "Jack-Tor", "The Source Awards", "Cleveland", "Jack Gets in the Game", Episode 210, "Subway Hero", "Sandwich Day", "Believe in the Stars", and "Generalissimo". This was Millicent Shelton's first 30 Rock directed episode, and would later return to helm the fourth season episode "Floyd".