This is a list of characters from the Nickelodeon animated TV series Hey Arnold!, where most residents live in the fictional coastal city of Hillwood, in the state of Washington.
Main characters Arnold Shortman
Arnold Phillip Shortman (voiced by J.D. Daniels in the pilot, Lane Toran in season 1, Phillip Van Dyke in seasons 2–3, Spencer Klein in season 4, most of season 5, and Hey Arnold! The Movie, Rusty Flood voiced young Arnold in Parents Day (season 3) and Helga on the Couch (season 4), Alex D. Linz towards the end of Season 5, Mason Vale Cotton in Hey Arnold!: The Jungle Movie, Zane VanWicklyn in Nickelodeon Extreme Tennis and Nickelodeon Kart Racers 3: Slime Speedway, and Logan Bailey in Paramount+ commercials) is the titular protagonist of the series. He is a 9-year-old dreamer and an idealist who is wise beyond his years, and who always tries to see the best in people and do the right thing. His parents, Miles and Stella, left to go to San Lorenzo when he was almost two years old but never came back to Hillwood. Whenever he sees someone in trouble, especially Helga, Arnold goes out of his way to help them out, even if it is not sensible to do so. Arnold often acts as the stable center to those around him, whether he is around his "family" in his paternal grandparents' boarding house, or around his friends at school. He lives in Sunset Arms boarding house with his grandparents, Phil and Gertrude.
Arnold has two major crushes in the series; one on sixth-grader Ruth McDougal (through most of season 1) and one on a classmate named Lila Sawyer (from season 3–5). However, his most catalytic relationship is with his classmate and frenemy Helga Pataki. Helga is secretly in love with him, though to keep these feelings secret she bullies Arnold. Arnold is completely unaware of this fact for most of the series, other than the occasional hint from Helga and other classmates. Helga reveals her secret to Arnold during Hey Arnold! The Movie, but Arnold allows Helga to take back her confession, attributing it to "the heat of the moment". In the made-for-TV sequel Hey Arnold! The Jungle Movie, Arnold returns Helga's feelings with a kiss of his own, after thanking Helga for her help in finding his parents and using her locket to help activate the device that releases the cure to the sleeping sickness which his parents had contracted before they could release the cure. It is also implied at the end of the movie that he and Helga become a couple, as Arnold holds hands with Helga (although Helga pretends to be hostile to Arnold at once in public). Arnold is friends with most of his fellow fourth-graders, with his best friend being Gerald Johanssen, whose friendship dates as far back as preschool.
Helga Pataki
Helga Geraldine Pataki (voiced by Francesca Marie Smith) is a 9-year-old rough and cynical girl who puts on a mean-spirited, rude, deceitful, and tomboyish front. She is often portrayed as the local bully and as Arnold's arch-rival yet love interest. She constantly bullies Arnold and other people, yet secretly loves him, which is obsessive to the point where she has made many shrines dedicated to him. She is an academically gifted student and a talented writer of poetry for her age. She pretends to despise Arnold because he is a good influence, and often remarks about his football-shaped head (despite most characters having different head shapes). Helga is also known for her catchword, "criminy!", which she normally exclaims when stressed. She becomes the antagonist in some episodes and occasionally expresses interest in pursuing the latter as a career. The reason for this is that she is neglected by her parents and often disrespectfully calls them by their first names because she does not think they are worthy of being called "Mom" and "Dad". Well, almost not at least. Her mother, Miriam, is usually depressed, forgetful, struggling to stay conscious, and frequently drinks what are implied to be alcoholic beverages, despite her referring to them as "smoothies". Helga relates very poorly to her. Her father, Bob, a successful pager salesman, who suffers from workaholism, rarely notices her existence, favoring her over-achieving, neurotic college-aged sister Olga, whom Helga rarely gets along with. He never listens to Helga. Ironically, it was Arnold who helped her during preschool, as she was explaining that she would have gone crazy if it wasn't for his kindness during her therapy session with Dr. Bliss
Helga resents her older sister, Olga, a perfectionist in her young adulthood. Although Helga will do her best to avoid unnecessary contact with Olga, she has shown feelings of love for her sister from time to time, as in the episode "Olga Gets Engaged", when she intervenes on Olga's behalf, saving her from what would have been a bad marriage, and "Big Sis" when she reveals her jealousy of Olga's relationship with Lila. In the episode "Quality Time", it is revealed that she hates corn and is allergic to strawberries because they give her hives.
In The Jungle Movie, she is shown to have an extensive video library of Arnold which she and Phoebe convince Gerald to use for the contest for the class field trip that Arnold hoped to win to search for his parents, which proves successful. During the trip, Helga attempts to express her true feelings to Arnold, who is not in the right frame of mind to hear it at the time and leaves abruptly. This leaves Helga heartbroken, to the point she rips up the picture of Arnold in her locket which she discards along with its fragments in the river. She briefly becomes angry at Arnold after the class is captured by Lasombra. When she sees Arnold crying quietly while looking at a picture of his parents, she forgives him and reaches for her locket for the picture, only for her to remember she discarded it. Although, she finds that Arnold's torn picture was recovered and repaired by Brainy. She convinces Gerald to help her free Arnold so they can reach the Green Eyes before Lasombra gets there first. Together with Arnold and Gerald, they manage to find the Green Eyes. Helga also comes up with the idea to use her locket to replace the Corazon which was lost while they were struggling with Lasombra, which activates the mechanism to release the cure to the sleeping sickness curing the afflicted Green Eyes and Arnold's parents. While she was attempting to retrieve her locket, Arnold thanked her for all she did and returned her feelings, resulting in them kissing, only to be interrupted by Gerald. At the end of the movie, while it is implied that she and Arnold are now a couple, she reverts to her old ways. When Arnold tries to hold her hand on the way to school with Gerald and Phoebe but secretly likes that Arnold makes that attempt, and Arnold, now knowing how she thinks, is content to go along with it; she is only feigning hostility towards him in public to maintain her tough girl reputation.
Series creator Craig Bartlett revealed in a 2018 interview that Helga's appearance was inspired in part by a young Frida Kahlo.
Gerald Johanssen
Gerald Martin Johanssen (voiced by Jamil Walker Smith throughout the original series and Hey Arnold! The Movie, Benjamin Flores Jr. in Hey Arnold! The Jungle Movie, Remond Francois in Nicktoons Nick Tunes, and Ramone Hamilton in Nickelodeon Kart Racers 3: Slime Speedway and Nickelodeon All-Star Brawl 2) is a 9-year-old boy and Arnold's best friend. He is an athletic and street-smart boy who is portrayed as loyal, though much less responsible than Arnold. Gerald is shown to have known Arnold for many years, most likely since preschool. Besides being Arnold's friend, Gerald also has knowledge of many legendary stories in the city, or "urban legends" as he calls them. He gets these myths from a source he has nicknamed "Fuzzy Slippers", mentioned in many episodes as his reliable assistant.
At school, Gerald is the class president and considers himself "very cool", and it is shown that his friends agree. When it was revealed that Arnold was on Rhonda's so-called "Cool List", and that Gerald was on her other list known as "The Geek List" (due to a grudge Rhonda had against him over running for class president), many classmates were surprised to find this out ("Cool Party").
His most distinct features are his tall, Kid 'n Play-style hair, and his shirt with the number 33 on it (he also wears 33 on sports uniforms). He has a crush on Phoebe, who shares the same feelings for him. At the end of Hey Arnold!: The Jungle Movie they are seen holding hands.
Supporting characters Phoebe Marie Heyerdahl (voiced by Anndi McAfee) is the smartest girl in Arnold's class. She is Helga's 9-10-year-old best friend and confidante, though Helga tends to boss her around for some reason. Nevertheless, Phoebe acts sometimes as Helga's moral compass, advising her on what she should do. Her ethnicity is half-Japanese, half-European on her father's side and her mother is European-American (White Southerner), and she hails from Kentucky. Being the smartest girl in her class is very important to her, and she tries her hardest to keep the status. Throughout the series, both she and Gerald have an interest in one another, with Gerald implying a crush on her during Rhonda's party in the episode "Hey Harold". In Hey Arnold!: The Jungle Movie, Phoebe kisses Gerald on the cheek and is both seen holding hands at the movie's end, having finally confessed their feelings for one another. Harold Berman (voiced by Justin Shenkarow) is an overweight Jewish American friend of Arnold. Although portrayed as the school bully during the first season, he became more of a companion to Arnold and the other kids later on as his antagonistic role increasingly shifted over to Wolfgang. Despite his frequent bullying and intimidation of other students, Harold's bullying never involves stealing lunch money; he is often revealed to be rather cowardly and usually cries for his mother whenever he gets scared or upset. He is sometimes referred to by the derisive nickname "Fat Boy", usually by Helga. Later episodes reveal that Harold has a soft spot. His best friends are Sid and Stinky. He works at the butcher shop after being hired as an apprentice. Stinky Peterson (sometimes spelled Petersen) (voiced by Christopher Walberg in the series, Jet Jurgensmeyer in The Jungle Movie) is a tall and lanky friend of Arnold's whose family is from Arkansas, and he is also one of Harold's best friends. Stinky has a Southern accent and a love for lemon pudding. His friendship with Harold had him originally portrayed in the first season as a bully and a sidekick of Harold's, though the former was later de-emphasized and he was reinvented as a more affectionate, mild-mannered, and romantic character viewed as the class "ladies' man", as he is romantically attracted to several female characters. He is shown to make up poems while Phoebe is feeling depressed. He shares a name with a character from Recess and from The Red Green Show. Sid (voiced by Sam Gifaldi in most episodes, Taylor Gifaldi in "April Fool's Day", and Aiden Lewandowski in The Jungle Movie) is a 9-10-year-old friend of Arnold and one of Harold's best friends with paranoid tendencies. He is always shown wearing a green baseball cap backward, a black leather jacket, jeans, and a pair of white Beatle boots. He often tells urban legends, with or without the assistance of Gerald. Perhaps his most well-known characteristic is that he typically ends up in ridiculous situations, such as becoming severely mysophobic, deciding to devote his life to Arnold after Arnold saves his life, and believing Stinky is a vampire, among other things.