The entertainment industry is mourning the profound loss of Kelley Mack, the versatile actress, producer, and voice artist, who passed away on August 2 at the age of 33. Her agent, Julie Smith, confirmed the heartbreaking news to USA TODAY on August 5, bringing a wave of sorrow across Hollywood and among her dedicated fanbase. Mack, born Kelley Lynne Klebenow, succumbed to a battle with glioma of the central nervous system in her hometown of Cincinnati. Her passing leaves an indelible void, remembered as a vibrant spirit who touched many lives, both on and off screen.
Mack’s journey into the world of storytelling began at a remarkably young age, fueled by a simple yet profound gift: a mini video camera. This early passion for capturing narratives blossomed into an impressive career, starting with appearances in commercials as a child. Her innate talent was quickly recognized, setting the stage for a promising future in film and television.
Her academic pursuits further honed her craft; Mack was a distinguished graduate of Chapman University’s Dodge College of Film and Media Arts, where she earned a bachelor’s degree in cinematography in 2014. Prior to her university studies, she attended Hinsdale Central High School. Her dedication to acting was also acknowledged early on, receiving an Acting Award from Tisch School of the Arts for her debut cinematic role.
That debut came in the 2008 independent film *The Elephant Garden*, where she portrayed the character of Chloe. This foundational role not only garnered her an Acting Award from Tisch School of the Arts but also contributed to the film winning the esteemed Student Visionary Award at the Tribeca Film Festival. It was a remarkable beginning for an artist destined for greater recognition.
Kelley Mack truly gained widespread attention for her compelling work in television, most notably her role as Addy in season nine of AMC’s critically acclaimed post-apocalyptic drama, *The Walking Dead*. Appearing in five episodes during the 2018-2019 season, her character Addy became intricately involved in the show’s gripping narrative, notably among the group of characters abducted by the Whisperers, which led to deadly results in the season finale.
Beyond the zombie apocalypse, Mack showcased her range in other prominent television series. She recurred on season eight of *Chicago Med* as Penelope Jacobs, a role that further demonstrated her ability to inhabit diverse characters within medical drama. Her television credits also included a cameo on FOX’s procedural drama *9-1-1* in 2019, adding to her growing list of notable appearances.
Her versatile performances extended to other popular shows, including guest shots on *Schooled*, a spinoff of *Modern Family*, and multiple miniseries. Mack’s ability to seamlessly transition between different genres and character types underscored her talent and dedication, making her a sought-after presence in the demanding landscape of television production.
In the realm of feature films, Kelley Mack’s career was equally vibrant and diverse. She captivated audiences with her role as Alice in *Broadcast Signal Intrusion* in 2021, where she starred opposite Harry Shum Jr. Her filmography also included appearances in *Mr. Manhattan* and the upcoming *Delicate Arch*, set for release in 2024.
One of her most anticipated upcoming projects was the feature film *Universal*, in which she not only starred but also served as an executive producer. This significant dual role highlighted her burgeoning capabilities behind the camera, showcasing her growing influence in the production side of filmmaking. The film was slated to be screened at the Portland Festival of Cinema, Animation and Technology on August 10 and the Chain NYC Film Festival on August 11, marking a poignant moment for her work to be showcased posthumously.
Mack’s artistic contributions were not limited to on-screen performances; she also left an indelible mark as a voice-over artist. Perhaps her most widely recognized voice role was serving as the voice match for Hailee Steinfeld’s Gwen Stacy in the Oscar-winning animated hit *Spider-Man: Into the Spider-Verse*. Her voice could also be heard in numerous commercials for national brands, including Dr. Pepper, Ross stores, Dairy Queen, and Chick-fil-A.
Her creative prowess extended further into the realm of production, writing, and directing. Mack held five producer credits during her career, including producing the 2016 short film *A Knock at the Door*. This project received critical acclaim, winning the Festival Award at the Atlanta Horror Film Festival and earning a pair of nominations at FilmQuest, solidifying her reputation as a formidable talent behind the scenes.
Demonstrating her comprehensive filmmaking skills, Mack wrote, directed, and edited the 2015 short film *Positive*, showcasing her singular artistic vision. She also contributed her technical expertise as a cinematographer on the 2014 short film *The Kingdom*. Additionally, she pursued screenwriting, often collaborating with her mother, Kristen, reflecting a shared passion for storytelling within her family.
Kelley Mack’s final months were marked by a courageous battle with a rare and aggressive form of cancer, specifically diffuse midline glioma, an astrocytoma that affects the central nervous system. Her health journey became public in a January Instagram post, where she bravely shared the personal struggles she had been enduring since the previous autumn.
She detailed experiencing persistent lower back pain starting in September, followed by neuropathic itching in her right quad. The severity of her condition escalated with the onset of shooting pains in her legs and back, which necessitated her sleeping in a recliner for a month due to the excruciating discomfort of lying down. Emergency MRIs performed in November revealed an abnormal mass on her spinal cord, leading to the devastating diagnosis.
The biopsy surgery on her spinal cord had a profound physical impact, causing her to lose the use of her right leg and most of her left leg. Consequently, she relied on a walker and a wheelchair for mobility, adapting to the significant changes in her daily life with immense fortitude. Despite the physical challenges, her spirit remained unbroken.
Throughout her treatment, which included proton radiation therapy, Mack expressed immense gratitude for the unwavering support of her loved ones. She completed her proton radiation treatment in March, or April, as some sources indicated, a testament to her resilience. In an Instagram update from Florida, where she received treatment, she reflected on the difficulties of adjusting to a new environment.
“It’s tough adjusting to a new environment after getting into a routine at home, but the mental and emotional support from my loved ones keeps me in check, even when I’m feeling physically out of whack,” she wrote, openly sharing her vulnerability. Her words resonated deeply with many, highlighting the profound strength she drew from her support system.
She viewed her health challenge as an opportunity for growth, stating, “It’s a challenge that’s really good for me, and the sun has been shining every day so far.” She remained hopeful despite the arduous path, acknowledging, “Overall, this journey has not been easy, but things are getting better — improvements are tough to see when you’re in the thick of it.” Her enduring optimism was palpable even amidst the most trying circumstances.
In another poignant reflection, she expressed the deep emotional and physical toll the illness took, yet maintained a profound sense of peace. “It has been a very emotional and challenging time, truly testing my mental fortitude, faith, and physical strength,” she shared. Despite the immense pressure, she found solace and determination, affirming, “They are so positive and we have a sense of calm knowing that my healing is taking place and we will overcome.”
According to the National Cancer Institute, gliomas are a group of tumors that form from abnormal glial cells, which are crucial for supporting and protecting the brain’s nerve cells. These tumors are found in the brain and spinal cord and are considered the most common type of malignant primary brain tumor in adults. Mack’s specific diagnosis, diffuse midline glioma, is an extremely rare subtype of glial tumors, originating in the primary central nervous system.
The National Cancer Institute estimates that approximately 3,940 people in the U.S. live with diffuse midline gliomas. Symptoms associated with these tumors can include double vision, swallowing problems, and a loss of balance or weakness on one or both sides of the body. Treatment options typically involve surgery, chemotherapy, radiation, or targeted medications, though the relative five-year survival rate for diffuse midline gliomas is noted as 42.2 percent, with survival depending on factors such as age and tumor grade.
News of Mack’s passing was initially shared by her sister, Kathryn Klebenow, in a heartfelt Instagram post on August 5. The tribute conveyed the profound grief felt by her family: “It is with indelible sadness that we are announcing the passing of our dear Kelley. Such a bright, fervent light has transitioned to the beyond, where we all eventually must go.” The post revealed that Mack “passed peacefully on Saturday evening with her loving mother Kristen and steadfast aunt Karen present,” surrounded by love in her final moments.
