Plot summary

The film starts at a white supremacist rally where journalist Fred Flarsky (Seth Rogen) is attending while undercover to expose the group. As he is in the middle of reluctantly getting a swastika tattoo on his arm, some of the members quickly discover that Fred writes expository pieces for a news site, The Brooklyn Advocate, and that he is also Jewish. Fred grabs his phone that has been recording them the whole time and leaps out a window, hitting a car outside as he lands, but still managing to hold onto his phone and he gets away.In the next scene, we meet Secretary of State Charlotte Field (Charlize Theron) as she enters a meeting with President Chambers (Bob Odenkirk), an actor who actually did play the POTUS on TV before going into politics. He tells Charlotte he wants to transition from TV roles to film, and he is looking for a replacement, despite only being in the middle of his first term. Charlotte smooth-talks her way to convince Chambers that endorsing a female candidate for president would leave him with a great legacy before leaving, and so he decides to give her his endorsement. Charlotte soon meets with her staffers Maggie (June Diane Raphael), Tom (Ravi Patel), and polling team manager Katherine (Lisa Kudrow) to help Charlotte with her campaign.Fred brings his piece on white supremacy to his boss (Randall Park), who tells Fred that The Advocate has been bought out by billionaire media mogul Parker Wembley (Andy Serkis). Fred hates Wembley and everything he represents, and Fred feels that he would turn their paper into a propaganda machine. He promptly quits, in spite of knowing he has no job prospects.Fred calls his best friend Lance (O'Shea Jackson Jr.) to cheer him up. Lance, who is a manager in his company, leaves for the day to help his buddy. That night, they attend an event to see Boyz II Men. It turns out that Charlotte is also there with Maggie and Tom. She and Fred spot each other among the crowd, but Fred freaks out upon seeing Charlotte. He goes outside where Lance follows him and asks how he knows her. Fred admits that Charlotte was his babysitter when he was 13 and she was 16, and he had a huge crush on her. He has an unfortunate memory of listening to her recite a speech for her campaign for class presidency, but he got overzealous and kissed her, which led to him getting an erection in front of her and her awkwardly telling him it's fine, right before her boyfriend came in and made fun of Fred's erection. He also later learned that Charlotte lost to a guy who ran on a two-prom system. Charlotte's bodyguard then steps outside to tell Fred that Charlotte wants to see him. The two chat as she remembers Fred, but they are interrupted by Wembley. After Charlotte leaves, Fred confronts Wembley and makes his hatred for him known, just moments before he trips and falls all the way down the stairs. And the video of him doing that goes viral.On the way back from the event, Charlotte tells Maggie and Tom how she knew Fred, and Tom mentions he likes some of what Fred has written. Charlotte then considers Fred to be her speechwriter since she thinks he's a good writer and could potentially bring a boost to her campaign. Maggie later gives Fred a call and invites him to join them and he agrees. He is soon picked up and taken to Washington D.C.Fred meets with Charlotte as she is preparing to go to an environmental summit to pitch an initiative to lend a hand in helping the planet, while also seeing it as her opportunity to launch her 2020 presidential campaign. Fred is hesitant as he is not sure whether or not Charlotte's plan will work, but she is very confident that it will, and so he joins the team.On their trip, Fred gives Charlotte a speech and adds tips on how she can seem more accessible to voters. They arrive in Sweden for the summit, where Fred is forced to wear a traditional Swedish men's suit that makes him look ridiculous. He finds out from Maggie that Charlotte has to change things in the speech, so he makes a scene trying to run and get the laptop to prevent her from doing so, only to toss his own laptop into the snow. Charlotte comes out to confront him for his behavior, but Fred asserts that this is what he was hoping to avoid when he signed on, since he wanted to work for someone who stuck to their guns. Charlotte argues that she has to play by the rules in order to keep herself in the game. Eventually, Charlotte delivers her speech without changing a thing, and it is a hit.Fred stays on Charlotte's campaign tour as he continues to write for her, and they start to get closer as they learn more about each other. They are in Buenos Aires one night where they appear to get closer and more intimately, but they are interrupted when insurgents begin attacking outside. Charlotte and Fred are brought by her security detail to a private bunker. Fred freaks out, but Charlotte teaches him a breathing technique to calm him down. They sit next to each other where they kiss before a guard comes to get them. After being taken out, Charlotte brings Fred back to her room for sex, though it lasts barely 10 seconds as they finish at the same time.Maggie quickly learns that Fred and Charlotte and sleeping together, and she tells Fred that the public won't accept them as a couple, but he doesn't care. During an event, Charlotte is courted by Canadian Prime Minister James Steward (Alexander Skarsgard), who is said by Charlotte's staff to be a viable bachelor. However, Charlotte finds Fred outside and the two share a private dance.Charlotte is later contacted by Chambers, who wants her to shut down her environmental initiative since he is partnering with Wembley, and it's an issue that he is not concerned with. She vents about this to Fred and asks that he help her get fucked up to let off steam. He takes her out to drink and get high off of molly, but Charlotte is soon called to handle a hostage negotiation despite being very high. Charlotte comes in with a relaxed demeanor and talks to the captor over the phone, relating to him on a personal level about how they don't want to deal with their pain-in-the-ass bosses. The negotiation is a success, which does wonders for Charlotte's numbers. During a televised speech, she lies and says that Chambers signed off on her initiative.Charlotte is brought in to meet with Chambers and Wembley following her TV appearance. Clearly not happy over what she said, they decide to blackmail her with a hacked video from Fred's webcam showing him talking to her about a speech before he starts masturbating and then ejaculates in his beard. Charlotte brings this news to Fred and mentions being blackmailed. Not only do Chambers and Wembley want Charlotte to go by their desires, but they want to give Fred an image overhaul so that he won't embarrass Charlotte. She also considers dropping her initiative if it means she has a better chance of winning. He doesn't want to go through with it despite Charlotte insisting that it's how she will win. They can't come to an agreement, so they break up.Fred goes back to Lance after his break-up and learns that Lance is a Republican and Christian after Fred mocks them. Fred reacts with disgust, but Lance calls him out and says that he didn't bring this up to him because he knew he would react that way, and it is his narrow-minded way of thinking that hurt his relationship with Charlotte. Meanwhile, Charlotte attempts to spend time with Steward for publicity, but he turns out to be charmless.Charlotte is up to give a speech during a conference. As she starts, she seems to go with Chambers's plan, but she realizes that her younger self would be disappointed in her for not sticking to her beliefs, and so she calls out both Chambers and Wembley, calling them idiots and talking about the jerk-off video in full detail before they put it online, but Wembley orders the video to be put up anyway. Charlotte's speech earns her applause before she is driven to meet with Fred. They reconcile and kiss before finally going public with their relationship, and they are warmly welcomed by the public.Sometime later, Charlotte is sworn in as the first female president of the USA, with Fred being her "First Mister" (or "First Man"). Although he continues to be unfiltered around her, he vows to stay by her side and support her throughout her presidency.