"False Advertising" is the fifth episode of the Durarara!! anime.
The episode opens in flash-forward with a mysterious person stabbing Celty Sturluson in the arm as she chases a man with a briefcase. At Raira Academy, Masaomi Kida hits on Anri Sonohara while she and Mikado Ryuugamine discuss recent events. Masaomi offers to be Anri's boyfriend, but accepts being in a love triangle with Mikado and Anri.
Takashi Nasujima stops Anri in the hall and says he's concerned for her because Mika Harima hasn't come to school yet. He assures Anri that she can tell him anything and reveals that he arranged for Mika and Anri to be in the same class, then puts his arm around Anri and tells her to be careful because the Slasher has been making appearances lately. Masaomi sees them and asks if Nasujima is sexually harassing Anri, so Nasujima leaves. As Masaomi talks to Anri, Mikado arrives and the trio walks to a nearby park.
After getting Mikado and Anri ice cream, Masaomi warns her that Nasujima had been dating a second-year student, Haruna Niekawa, who transferred out of Raira this year. Mikado asks Anri about the bullies from her junior high, having heard from their earlier conversation with Anri that they bullied her because her friend Mika Harima was gone. Anri says Mika has been missing since before school started, and the only thing she left was a text to Anri and her own parents saying her heart was broken and she had gone on a trip. Anri shows Mikado and Masaomi a picture book of her and Mika and reveals that Mika was a stalker. Masaomi deduces Mika stalked Seiji Yagiri.
As Mikado is about to say Mika just used Anri to make herself look better, Anri says the same thing. She also admits to depending on Mika, but she now claims to be independent. The reason she chose to be class rep was because that was the job Mika wanted, and Anri wanted to prove that she could be better than Mika. Mikado understands that by her telling them, she was asking for their forgiveness, but he assures her that she doesn't need to be forgiven for wanting to be better. Anri thanks Mikado for his understanding, and a laughing Masaomi pushes his friend off the park bench.
Mikado talks with Masaomi about wanting to find Mika and Seiji. Masaomi tells him he would need a huge organization to do that, so Mikado suggests the Dollars. Masaomi stares at his friend in shock and asks him if he is seriously considering joining the Dollars, which Mikado denies. Masaomi promises himself that he would never allow Mikado to see the darkness Ikebukuro holds. As the two part ways, Masaomi walks by a large building, where he stares at an upper-story window before turning and walking away. A girl inside in a hospital gown sits on a hospital bed staring out at him.Simon Brezhnev, Izaya Orihara, the Dollars, and Shizuo Heiwajima. Someone says it used to be the color gang known as the Yellow Scarves until they had a huge gang war with the Blue Squares and both gangs disintegrated, but now they're back. Kyouhei Kadota, Walker Yumasaki, Erika Karisawa, and Saburo Togusa are discussing the same gang war in Russia Sushi. Masaomi enters the restaurant and asks them for advice on how to keep a friend of his from the Dollars.
Mikado spots Seiji and a girl he thinks might be Mika while exiting a convenience store. He pursues them and is followed by two men in suits. When he calls out to Seiji, he is told off for interrupting their romantic getaway, but not before he notices that the girl does not look like Mika Harima.
After leaving Russia Sushi, Masaomi bumps into three members of the Yellow Scarves, who take him into an alleyway to beat him up. Mikado sees Masaomi and runs to him.As the events from the opening scene repeat, Mikado and Masaomi's attention is caught by a man running and yelling "Monster!" They use the distraction to make a break from the alleyway, narrowly missing the Slasher, which stops at the alleyway and cuts the Yellow Scarves members. Farther away, the two friends stop running and laugh about the crazy things that go on in Ikebukuro.Izaya visits a pale girl in a hospital. She is surprised and glad to see him, then tells Izaya that "he" hasn't visited yet and only walks to the sidewalk corner but never enters the hospital. Izaya says he's sure "he" will come. The girl's phone has a picture of her with Masaomi.
Niekawa returns to his home and asks Haruna to come down. Haruna is busily typing away on her computer.
While walking with his friends, Masaomi remarks that the three of them - he, Mikado, and Anri - have a friendship that can weather any storm.
A new person arrives in the chatroom and posts randomly, then leaves quickly. Kanra wonders if it was a troll, and Setton thinks it was an alien. Setton denies thinking aliens are scary, and TarouTanaka asks if she thinks the Slasher is not scary. Setton replies that the new person is. Later, Kanra says he banned the troll, then asks the chatroom if they heard that the Yellow Scarves were hit by the Slasher. TarouTanaka inquires as to what the Yellow Scarves and the Slasher are, but Kanra proceeds to ask, almost rhetorically, if the Slasher is with the Dollars.
- To Anri being bullied by three girls from her junior high
- To Mikado and Anri running from the fight between Shizuo, Izaya, and the gangsters
- To Anri stopping Seiji outside the school to ask him about Mika Harima
- While most of the events in this episode are adapted from the second light novel, some events are anime exclusive and others are pulled from the first and third light novels. This episode begins to introduce the second arc of the series.
Masaomi: "Mr. Nasujima, you sexually harassing her?"
Masaomi: "It may not look like it at first, but everything that happens in this town is somehow related. Itss all part of some larger, awful truth that's beyond our comprehension."