Sex
A major theme in the film is sexuality, the pursuit of sex, and extramarital affairs. From the start, we see that the reason that Baxter performs so well at work is because he is lending his apartment to higher-level executives so that they can carry on extramarital affairs in the city far from the snooping eyes of their suburban families. For a few hours, executives get to listen to festive cha cha music, pop champagne bottles, and have sex with any number of women. Baxter's neighbors mistake the constant sound of festivities and sex for evidence that Baxter is himself a sex maniac. In fact, he is never the one having sex in his own apartment. Sex is a rather lighthearted theme for the beginning of the film, as we see executives and mistresses who are exceedingly detached and unemotional about their own sexual affairs. As the movie progresses, we see that sex and its attendant emotions have greater repercussions, as shown through Fran's heartsick relationship with Sheldrake, his cavalier rejection of her, and her attempted suicide.
"He's a taker"
When Fran is recuperating at Baxter's apartment, she discusses the fact that she is still desperately in love with Sheldrake in spite of the way that he has mistreated her. She describes Sheldrake as a "taker," saying, "Some people take, some people get took. And they know they're getting took and there's nothing they can do about it." Fran sees that Sheldrake can do unethical things and hurt people, but it bears no consequence on their lives and they still end up on top. Sheldrake and the other executives treat their families and their mistresses horribly, but they are never punished for it. Indeed it is precisely their ability to be remorseless about their bad deeds that gives them so much power. In Fran's eyes, she and Baxter are people who "get took," who never have the power. By the end of the film, Baxter has stood up for what he believes in and has left the company, and he is no longer "getting took." Thus, power and how powerful people exploit the less-powerful is a major theme in the film.
Loneliness
Even though his neighbor Mr. Dreyfuss thinks he is a real ladies' man and hard partier, Baxter is quite a lonely person. The fact that he gives out his apartment to his coworkers means that he has to stay late at the office and kill time out of the house to give them time to carry on their affairs. He ends up living a very solitary life with few friends or companions. Even when he gets home, he is all the more lonely, heating up a pathetic dinner and eating it in front of the television. Thus, we see that even though Baxter is ostensibly living the dream by working at a high-powered office in New York City and living on the Upper West Side, the reality of his existence is actually quite lonely and solitary. It is not until he meets Fran that he begins to open up and find human connection.
Alienation
In line with the theme of loneliness is the broader theme of alienation. The characters wander around a corporate jungle in which employees are defined by their positions and the amount of power that they have in those positions. Baxter is one of many employees, and they all work in equally spaced, uniform rows of desks with typewriters atop them. It is a sea of office supplies, paper, and typewriters, and Baxter is an easily replaceable cog in a faceless machine. People pour in and out of the lobby everyday, on their way to and from their lives of corporate drudgery. This repetitive professional lifestyle is undeniably alienating, and the plot follows the protagonist Baxter as he seeks to find autonomy and connection in spite of the pervasive alienation of office life.
"Be a Mensch"
Misinterpreting the heavy traffic in and out of Baxter's apartment for evidence of Baxter's hard-partying lifestyle, the older and wiser Dr. Dreyfuss advises him to slow down his lifestyle before it gets away from him. His central advice to Baxter is to "be a mensch," which is to say that he should be a more responsible and good person, connected to his own humanity and standards. In many ways, the call to "be a mensch" contrasts the corporate ethic that Baxter is caught in, with all its deceptions and dishonors. Thus, Baxter's journey in the film is defined by this call to "be a mensch," and indeed, when he quits his position as Sheldrake's assistant, realizing that he doesn't respect Sheldrake enough to work for him, he tells his boss, "I've decided to become a mensch!" Sheldrake doesn't know what he's talking about, but that hardly matters; for the first time, Baxter has decided to follow his own authority.
Suicide
Fran and Baxter seem to share a certain heartfelt and earnest character that is somewhat anomalous in their otherwise detached corporate circles. Both seem to feel more deeply and care about people more than their counterparts. This emotional quality imbues them with compassion and charm, but it also makes them more vulnerable to getting hurt. Indeed, another thing the two of them share is that they have both attempted suicide. After Sheldrake leaves her on Christmas Eve with nothing more than $100 and an empty promise to leave his wife, Fran downs a bottle of sleeping pills. Even after she is revived, she expressed to Baxter that she cannot help but love Sheldrake, almost as though she is in thrall to her own rejection. Baxter shares his own story of heartbreak, in which he had an affair with a friend's wife, she rejected him, and he tried to shoot himself, but ended up accidentally shooting himself in the knee. Both these characters share the quality of wearing their hearts on their sleeves to such an extent that they lay themselves vulnerable to getting hurt. Suicide is one of the darker themes in a film that maintains an otherwise lighthearted tone.
Betrayal
Part of what makes Sheldrake such a despicable villain is the fact that there is seemingly no one in his life that he won't betray. He keeps his affair with Fran hidden from his wife and family, and he lies to Fran about planning to leave his wife. He commits these betrayals without a second thought, and treats them as a privilege of his powerful position in the corporate ladder, bolstered by the affirmation of his patriarchal network of coworkers. Thus betrayal and deception are at the center of the film's conflict and are an important theme. The reason Fran feels so hurt by Sheldrake and is driven to attempt suicide is that Sheldrake is such a remorseless liar and has led her on, which makes her feel cheap and worthless.
