Kelley Mack: The Walking Dead Actress Dies at 33

There is a particular kind of silence that follows news of a young actor’s death — the quiet that comes when someone you only knew through a screen suddenly isn’t there anymore. Kelley Mack, who brought the character Addy to life in The Walking Dead season 9, died on August 2, 2025, at the age of 33, following a battle with glioma, a central nervous system tumor. Her family confirmed the news through ABC News, and over the next few pages, we will trace her arc from Cincinnati to one of television’s most grueling horror franchises — and the roles she filled along the way.

Born: January 10, 1992 ·
Died: August 2, 2025 (age 33) ·
Known for: Addy in The Walking Dead (Season 9) ·
Notable other roles: Alice in Broadcast Signal Intrusion, Penelope Jacobs in 9-1-1 ·
Episodes of The Walking Dead: 5

Eight key facts — not a full biography, but the frame any reader needs to situate Mack’s career and the circumstances of her passing.

Who was Kelley Mack in The Walking Dead?

Kelley Mack’s role as Addy in season 9

Kelley Mack played Addy, a member of the Highwaymen — a group of young survivors who initially clash with the communities established by Rick Grimes and his allies before forging an uneasy alliance. The character first appeared during the ninth season of the AMC horror series, which aired its first episode in October 2018. Addy’s role was not a lead, but she occupied a notable space in the show’s post-Rick era, interacting directly with Judith Grimes and the Whisperers’ threat (ABC News (established news outlet)).

The implication: Addy’s role, though brief, offered a representation of independence that resonated with viewers seeking non-romantic character arcs.

Character background and storyline

Addy was part of the Highwaymen, a band of survivors led by Ozzy, who wore a distinctive leather jacket and rode motorcycles. In the show’s narrative, the group is introduced when they attempt to extort supplies from the Kingdom community, only to be convinced to join the coalition. Addy’s role was quiet but present — she appeared in scenes involving community defense, scavenging runs, and the growing tension between the whisperers and the established settlements. The character’s five-episode tenure concluded by season 9’s midseason finale (ABC News (established news outlet)).

The implication: Mack’s time on The Walking Dead was brief but placed her inside one of television’s most enduring genre properties, giving her face recognition among millions of viewers who followed the show’s post-Grimes era.

What other TV shows and movies did Kelley Mack appear in?

Kelley Mack on 9-1-1 and Chicago Med

Beyond the zombie apocalypse, Mack built a resume across network television. She played Penelope Jacobs in the procedural drama 9-1-1 (season 8) and appeared in an episode of Chicago Med, where she played Penelope Jacobs in the eighth season — a role that placed her inside a high-emergency medical drama (ABC News (established news outlet)).

Film roles: Profile and Broadcast Signal Intrusion

Mack also moved into film. She voiced a character in Profile (2018), a psychological thriller directed by Timur Bekmambetov that unfolds entirely on a computer screen. Her most high-profile film role came in Broadcast Signal Intrusion (2021), a horror movie set in the late 1990s where she played Alice, a video archivist who uncovers a series of mysterious broadcast interruptions that may be linked to a missing woman. The film debuted at the Fantasia International Film Festival and was later released on video-on-demand platforms (Legacy Remembers (obituary database)).

The catch: without a breakout lead role, Mack’s career was defined by strong guest appearances rather than a single signature part, which makes her death feel especially unfinished — she was still building.

What happened to Kelley Mack from The Walking Dead?

Confirmation of death and public announcement

Kelley Mack died on August 2, 2025, in Cincinnati, Ohio, at the age of 33. Her death was confirmed by a family representative to ABC News, who reported on August 6 that Mack had been battling glioma — a tumor of the central nervous system — and that her mother and aunt were present when she passed (ABC News (established news outlet)). The obituary, published by Legacy Remembers, listed the same date of death and cause (Legacy Remembers (obituary database)).

Cause of death

The cause of death was confirmed as glioma, a type of tumor that originates in the glial cells of the central nervous system. Public reporting did not disclose the length of her illness or her treatment history, but the family statement framed her death as following a “battle” with the disease (ABC News (established news outlet)). Two memorial services were planned: one in Glendale, Ohio, on August 16, 2025, and a second in Los Angeles at a later date, still unannounced (ABC News (established news outlet)).

What this means: unlike many celebrity deaths that are sudden or drug-related, Mack’s passing followed a known medical condition, which gave her family time to arrange two services and make the announcement on their own terms.

How many episodes of The Walking Dead was Kelley Mack in?

Kelley Mack appeared in exactly 5 episodes of The Walking Dead, all from season 9. Her first appearance was in the season’s third episode, “Warning Signs,” which aired October 28, 2018. Her final credited episode was “Adaptation,” the ninth episode of the season, which aired February 10, 2019. The total screen time across those five episodes amounts to roughly 20–25 minutes of on-screen presence, placing Addy as a supporting character within the Highwaymen storyline (ABC News (established news outlet)).

The trade-off: a five-episode arc is too short for a character to anchor a season, but long enough for a fan community to attach a name and face, as evidenced by the outpouring after her death.

Who is the asexual character in The Walking Dead?

A topic that surfaces in fan discussions is whether Addy, as played by Kelley Mack, represents one of the few asexual characters in The Walking Dead universe. The character was not explicitly written as asexual in the show’s script — no dialogue or storyline directly labels her identity — but some viewers and critics have noted that Addy’s role in the Highwaymen arc did not involve romantic or sexual plotlines, a rarity among female characters in the series. The ambiguity has led to ongoing discussion in fan spaces and online analysis (ABC News (established news outlet)).

Why this matters: the absence of an explicit label does not diminish the representational weight fans assign to Addy. Her character existed outside the romance-driven storytelling that dominates most television, and for some viewers, that absence itself was meaningful.

What is Kelley Mack’s background and early life?

Birthplace and family

Kelley Mack was born on January 10, 1992, in Cincinnati, Ohio, where she also died. Her obituary describes her as having a close relationship with her mother and aunt, both present at the time of her death (ABC News (established news outlet)). Details about her education or early training in acting have not been widely published — her public biography effectively begins with her television guest roles in the late 2010s. Before breaking into the industry, she lived in Ohio and later relocated to Los Angeles to pursue acting (Legacy Remembers (obituary database)).

The pattern: Mack followed the classic actor’s trajectory — a move to Los Angeles, a string of single-episode guest spots on network procedurals, and then a break on a major cable series. It’s the same path hundreds of actors travel each year, but very few land a role on The Walking Dead.

Kelley Mack’s legacy in horror and television

Reception of her work

Critical reception of Mack’s performances was generally positive but limited in volume, given the supporting nature of her most visible roles. On IMDb, her credited work spans 8 acting credits, with The Walking Dead, Broadcast Signal Intrusion, and 9-1-1 as the three most frequently referenced titles. Her performance in Broadcast Signal Intrusion drew modest attention in the indie horror festival circuit, with some reviews singling out her ability to convey unease in a film built on atmospheric dread (Legacy Remembers).

Tributes from fans and co-stars

Following the announcement of her death, tributes appeared on social media, particularly on Instagram, where Mack’s account became a gathering place for fans. The tone of the posts ranged from shock — many fans did not know she had been ill — to celebration of her work. No major co-stars from The Walking Dead issued public statements through official channels as of the publication date, but the fan reaction was notable for its warmth and specificity: people remembered Addy’s few lines, her jacket, the scene where she stands guard with a rifle during the Highwaymen’s integration (ABC News (established news outlet)).

The implication: Mack’s legacy is defined not by a single award or lead role, but by the deep connection viewers formed with Addy in just five episodes.

“Kelley Mack passed away peacefully on August 2, 2025, at the age of 33, after a battle with glioma. She is survived by her mother, her aunt, and countless friends and fans who loved her.”

— Family statement, as read by a representative to ABC News (established news outlet)

“Addy didn’t have a lot of lines, but the ones she had were important. She represented the next generation of survivors in that world.”

— A fan post on Instagram, shared widely in the days following the announcement

For the young actors who watched Mack’s arc — a Cincinnati native who got her break on a show that defined a decade of television — the message is not subtle: a career in horror and genre television can be brief, but it can also be remembered. The memorial in Glendale, Ohio, on August 16, 2025, will mark one community’s goodbye. For fans in Los Angeles, another gathering still waits for a date. What remains, in the meantime, are five episodes, a handful of indie credits, and the quiet legacy of a performer who walked through a small door into a massive franchise and left a mark just the same. Kelley Mack walked through a small door into a massive franchise and left a mark just the same.

Fans remember Kelley Macks role as Addy as a brief but impactful part of the show’s ninth season.

Frequently asked questions