Seasons 1 and 2

Buffy is introduced to her new school as a student who is both emotionally and academically troubled. With the move to Sunnydale, she believes she is starting fresh, a notion her mother also believes and encourages.^[6] As Buffy establishes herself in school in early episodes, Joyce, who is recently divorced, is preoccupied with setting up their home and running an art gallery.^[7] Initially unwilling to become involved again with her role as the Slayer, Buffy is nevertheless confronted by the school librarian Giles (Anthony Head), her new Watcher, the mentor and teacher assigned to instruct her how to fight vampires and other demons she is destined to face. Buffy does not tell her mother about this development, and Joyce remains ignorant of Buffy's role as the Slayer and of Giles' influence in her life, something she later resents when he seems to be closer to Buffy in ways Joyce is not.^[8]

Joyce's initial role in the series is, according to scholar J. P. Williams, very similar to the Superman character Lois Lane, who is unable to discern the likeness between Clark Kent with his glasses on and Superman with his glasses off. Buffy is frequently referred to as a superhero by authors, and Joyce's initial ignorance of Buffy's abilities and responsibilities creates skepticism among both characters in the series and viewers about Joyce's intelligence and motivations.^[9] For example, Joyce sees the extremely attentive Giles merely as a teacher concerned about Buffy as a student who has experienced academic problems in the past.^[10]

This willful ignorance of Buffy's vocation has been well-analyzed by Buffy studies scholars. A persistent theme in Buffy is the nearly unbreachable generation gap between adolescents and adults. Throughout the series, adults are either unable or unwilling to see the genuine horrors teenagers face. As Buffy's mother, Joyce is repeatedly confronted with evidence of her daughter's role as the Slayer; Sutherland saw this as a form of denial on Joyce's part.^[5] The resulting conflict between Joyce and Buffy is both tragic and humorous. When Buffy skips class or stays out late to attend to her Slayer duties, Joyce is left trying to punish her by restricting her to the house. Joyce responds to the dire situations Buffy must face by placing regular and inconvenient restrictions on her, such as grounding her at a time when Buffy must confront and try to kill the Master (the head of a vampire cult who is attempting to fulfill a prophecy that he will kill the Slayer and open the Hellmouth in Sunnydale), saying sarcastically to Buffy, "I know—if you don't go out it'll be the end of the world", when in fact, it just may be,^[11] or telling Buffy that she is free to make her own life choices, when Buffy knows exactly what her destiny is, and that it may include dying young. This duality of language reinforces the generation gap between the characters.^[9]

Joyce is, according to author Lorna Jowett, a typical "teen-horror parent": loving and supporting, but not really facing or knowing the true extent of reality, therefore ineffective at helping her child.^[12] She embodies the expectation that mothers should intuitively understand their children.^[9] Buffy confronts her mother's denial in "Becoming", the second-season finale, forcing Joyce to see the reality of what Buffy is and does. As a result of their confrontation, Joyce gives Buffy an ultimatum that she either stay at home or never come back. As Buffy is compelled to thwart the apocalypse, she accepts her mother's decision, leaves the house and, ultimately, Sunnydale. Sutherland read the script for the second-season finale in her car, unable to stop reading until the resolution, where she sat sobbing when it is revealed Buffy leaves.^[4] In their heated encounter Buffy says to her mother, "Open your eyes, Mom. What do you think has been going on for the past two years? The fights? The weird occurrences. How many times have you washed blood out of my clothing and you still haven't figured it out?" Joyce responds by trying to restrict Buffy again, then attempting to physically restrain her, at which point Buffy ends Joyce's ideas of parental authority by easily overpowering her and walking out the door.^[12]

Despite her difficulty with understanding Buffy, Joyce frequently expresses her love for her daughter and supports her when other adults do not. The love Joyce expresses is interpreted by scholars as an attempt to compensate for having failed to understand intuitively that something was going on with her daughter before the revelation that Buffy is the Slayer. Following that revelation, Joyce makes many attempts to understand what a Slayer does. Many scenes showing Joyce giving love and support to Buffy take place in their home, establishing it as center of motherly devotion, stability, and safety. Shots are usually composed so that the two are not seen in the same frame, or are separated by objects such as tables, or placed in opposite sides of rooms, a visual representation of Joyce's inability to understand her daughter's responsibilities and powers.^[12]

Seasons 3 and 4

The third season opens with Buffy returning home from Los Angeles at the end of "Anne". Joyce and Buffy are at first very ill at ease with each other during the next episode, "Dead Man's Party", while Buffy starts to understand how difficult Joyce's time has been without her.^[13] Sutherland welcomed the change; she felt the relationship between Joyce and Buffy "became so much richer" after Joyce finally knew of and faced Buffy's role as the Slayer.^[5] The overt conflict of "Dead Man's Party" has Joyce bringing home a cursed mask that calls zombies to the house while a party is occurring, killing several people. Author Nikki Stafford sees the zombies at the party as symbolism for the utter confusion of dealing with Buffy's return.^[14] During the party, Buffy feels so uncomfortable around her family and friends she considers leaving again. Joyce and Buffy's best friend Willow Rosenberg (Alyson Hannigan) both angrily confront Buffy; Joyce admits that she does not know all the answers and that giving Buffy an ultimatum was a mistake. The episode marks Joyce's return as a parent; her recognition of her own shortcomings in the error of pushing Buffy away is a measure of nobility common among Joss Whedon's characters.^[12]

Following her realization that Buffy is the Slayer, Joyce begins to express concern for Buffy's well-being and long-term plans. The third season showcases two episodes in which Joyce is a major character. Both of them posit Buffy as a parent figure over Joyce. With "Band Candy" the episode begins with Buffy being petulant and Joyce working with Giles to create a schedule for studying and slaying, but these roles quickly dissolve in the ensuing chaos. In an attempt to offer a sacrifice to a demon, Sunnydale's shadowy mayor intoxicates the adults of the town with drugged chocolate bars, making them devolve into adolescents.^[15] Joyce descends into the behavior of a 16-year-old, a prospect Kristine Sutherland found not only fun, but painful as it brought back memories she had not faced in years.^[5] Giles is also affected, turning into his adolescent miscreant self, which Joyce finds irresistible (the two have sex on a police car in the middle of downtown Sunnydale).^[16] Giles has become Buffy's father figure following her parents' divorce, and Buffy finds Joyce's attraction to Giles disquieting. Joyce had dated before ("Ted") but Buffy, and consequently the audience, do not see Joyce as a sexual character; she is foremost a mother. According to Lorna Jowett, Joyce is rare among the characters on the series: "Joyce is always and only Buffy's mother, never just another person or a member of the team."^[12]

The second instance of role-reversal is in the episode "Gingerbread", where again children demonstrate more wisdom than the adults. The episode is noted as highlighting this motif specifically, as the divide between parents and children is exaggerated and symbolized by Joyce's confusion. In an attempt to learn more about her daughter's Slayer duties, Joyce follows Buffy on patrol at night, bringing snacks and saying she wants to observe Buffy work. Joyce finds two dead children in a playground and is deeply disturbed. After Buffy comforts her mother, the Scoobies discover that the children are the manifestation of a demon whose sole purpose is to tear communities apart by sparking moral panics. Joyce, meanwhile, becomes entirely consumed with finding the culprit of the apparent murders. She starts a parents' activist organization named "Mothers Opposed to the Occult" (or "M.O.O." to Buffy's mortification) with Willow's mother, an academic and parenting expert so self-involved that she virtually ignores her daughter. Both Buffy and Willow—whose skills in witchcraft are growing—are seized by M.O.O., who attempt to burn them at the stake.^[17][18] Joyce takes a leadership role, giving a speech to concerned parents about the unnatural evils in the town, citing the "slayers and witches" among other monsters. Her compulsion to become involved in Buffy's dark world, with its disastrous results, represents her feeling of helplessness in relation to Buffy's calling. She is unable to protect or comprehend what Buffy must endure—another expression of teenage-parent alienation.^{[12][19][note 1]}

In the fourth season, as Buffy and Willow attend college, Joyce's role is scaled back considerably. Kristine Sutherland and her family moved to Italy to live, so she starred in only five episodes in the season,^[5] including the first one, "The Freshman," when Buffy comes home during her bewildering first week at college to discover that Joyce has filled her room with packing crates from the art gallery. This sign of her mother's life going on without her increases Buffy's disorientation and underscores Joyce's independent life.^[20] Consequent to her mother's distance, Buffy must begin to face some of her problems alone, the least of which is cooking Thanksgiving dinner for Giles and the Scooby Gang in "Pangs". Buffy encounters a female psychology professor at college who challenges and frustrates her, but also validates her intellect, something Buffy has not been well known for. Professor Maggie Walsh becomes, for the first part of the season, a substitute mother for Buffy.^[9] The last episode of the season,"Restless", explores the dreams of Willow, Xander Harris (Nicholas Brendon), Giles, and Buffy. Joyce appears as a seductress to Xander (in a red silk nightgown), and appears again in Buffy's dream as Buffy wanders the halls of college. Joyce is stuck inside a wall, saying that she is content making lemonade and learning to play mahjong. The enigmatic nature of "Restless" allows analysts to explain the depth of the characters and their relationships, as well as the foreshadowing of events to come in subsequent seasons. Joyce's confinement in a tight space in Buffy's dream indicates that Buffy considers her mother's life to be very limited.^[9] The hole in the wall through which Joyce and Buffy speak briefly shows only Joyce's head and shoulders, which, according to Nikki Stafford, is the prevailing image in the fifth-season episode "The Body", an episode which explores Joyce's death and its immediate aftermath.^[21]

Season 5: Joyce's death

As noted by author Roz Kaveney, Joyce becomes central to the fifth season themes of family and Buffy facing forces she is unable to fight or control. A new character is introduced to the Summers family: Buffy gets a 14-year-old sister named Dawn (Michelle Trachtenberg), who is the mystical embodiment of a "key" which opens portals to all dimensions. Prior to Dawn's arrival, Joyce has been experiencing loneliness as Buffy's increasing responsibilities takes over, at one point remarking that her house gets very quiet without Buffy present. She inadvertently invites the Romanian vampire mystic Count Dracula as the result. Although Dawn is unaware of what she is, Buffy learns her true identity after becoming suspicious that Dawn is attempting to harm Joyce. After experiencing debilitating headaches, collapsing, then requiring hospitalization, Joyce learns that she has a brain tumor. A side-effect of the tumor is that Joyce sees Dawn as she truly is: a bright, beautiful, mystical energy that must be protected from harm.

Despite knowing the truth of Dawn's origins, Joyce still loves her, realizing that she is an innocent who belongs in the Summers family, and collaborates with Buffy and Giles to protect her. The spell which made Dawn human also made her biologically related to Joyce and Buffy. To protect Dawn as well as tend to Joyce after she has brain surgery, Buffy moves out of her dorm and returns to the family home. Riley Finn (Marc Blucas), Buffy's boyfriend for the past year, leaves in the episode "Into the Woods". Following his departure, and in the course of the episode "I Was Made to Love You", Buffy comes to feel that she does not need a boyfriend. Her confidence in this decision is immediately shaken at the end of the episode when she comes home to find her mother's lifeless body on the sofa. Joyce's death is fully explored in "The Body" as the entire cast of characters struggles to understand how the once-vibrant Joyce has become a body in the morgue.^[22][23][24] Scholar Jes Battis writes that in contrast to the way family members are portrayed throughout the series as absent (Willow's), chaotic (Xander's), or highly disruptive (Anya's), Joyce straddles these extremes. The ease of her success at mothering a violent superhero and a mystical key while appearing to enjoy a normal life is eroded by a brain tumor, and only then do she and the other characters come to understand what a complex job she has. To scholars the tumor represents the physical manifestation of not being able to take care of Buffy, or a form of mortality that Buffy will not soon face.^[25]

To Joss Whedon, the tumor represented nothing more than cancer. He planned to kill Joyce as early as the third season, and he wrote the episode to reflect what he experienced when he lost his own mother to a brain aneurysm. In 2001, Whedon told an interviewer, "I knew I was going to kill Joyce, and I knew that what I wanted to capture — because I had lost my own mother — was that weird dumb grief and the various reactions that people have to death."^[26] "The Body" begins with a Christmas dinner scene presided over by Joyce as the head of her chosen family. At the table are Buffy, Dawn, Giles, Willow, her girlfriend Tara (Amber Benson), Xander, and his ex-demon girlfriend Anya (Emma Caulfield). Pragmatically, the scene was included so the credits would not roll over the dramatic moments of Buffy finding her dead mother and trying to revive her. Whedon did not want to include any element that broke the illusion presented in the episode.^[27] In a realm where the main adolescent characters, who are becoming adults, must regularly face horrors and evils, Joyce represents a stable and predictable life. Her death crushes the illusion that real or normal life — which Buffy frequently says she wants but cannot have — is trouble-free.^[12] Joyce is mourned by all of the characters in the series. Even the amoral vampire Spike (James Marsters) expresses his condolences. In an earlier episode he had confided in a very sympathetic Joyce about his equally amoral and insane lover Drusilla (Juliet Landau) leaving him.^[28][29] Likewise, Anya, who has very little experience with human emotions and frailties, is confused and unexpectedly saddened by Joyce's death.^[30]