The Walsh Sisters is set to premiere on September 28, 2025, on RTÉ One, promising a heartfelt and authentic look into the lives of a contemporary Irish family. The series follows the five Walsh siblings—Claire, Rachel, Maggie, Anna, and Helen—as they navigate the tangled web of personal challenges, evolving relationships, and the complexities of modern life. Anchoring the chaotic lives of the sisters are their parents, Jack and Mammy Walsh. The show brings together a formidable mix of established Irish acting legends and exciting new talent. Let’s meet the family.

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The Walsh Sisters cast complete guide

1: Aidan Quinn as Jack “Daddy” Walsh

Aidan Quinn, born on March 8, 1959, in Chicago to Irish parents, has enjoyed a long and respected career in film and television since the 1980s. He first gained critical acclaim for his role in Desperately Seeking Susan (1985) and became a familiar face in dramas like The Mission (1986) and Benny & Joon (1993). On television, Quinn has anchored several major series, including his Emmy-nominated role in An Early Frost and his compelling performance as Captain Tommy Gregorio in Elementary. His ability to portray grounded, often paternal figures with a quiet strength makes him perfectly suited to play the family patriarch, Jack Walsh.

Quinn’s filmography is a testament to his versatility, spanning indie darlings like This Is My Father (1998) to blockbusters like Legends of the Fall (1994). His deep connection to his Irish heritage has often seen him cast in projects related to Ireland, bringing an inherent authenticity to such roles. As Jack “Daddy” Walsh, he is expected to be the steady rock amidst the storm of his five daughters’ lives. Quinn’s presence guarantees a performance filled with nuance, portraying a man grappling with the changing dynamics of his family and his role within it.

2: Louisa Harland as Anna Walsh

Louisa Harland, born in Dublin, skyrocketed to international fame with her scene-stealing performance as Orla McCool in the beloved Channel 4 series Derry Girls. Her portrayal of the eccentric, uniquely logical Orla made her a fan favourite and demonstrated her incredible talent for comedy with perfect timing and a deadpan delivery. Prior to this breakout role, Harland honed her craft at the Oxford School of Drama and appeared in other television projects like Riviera, but it was Derry Girls that cemented her status as a rising star of Irish acting.

Harland’s move from the 1990s Troubles-era Derry to modern-day Dublin as Anna Walsh in The Walsh Sisters is a highly anticipated next step. While Orla was often the source of comic relief, the role of Anna Walsh is expected to showcase a broader emotional range. This part will allow Harland to explore a more complex character, likely one of the younger sisters finding her way in the world. Her casting promises a performance filled with the same authenticity and charisma, but with new depths to be discovered.

3: Danielle Galligan as Claire Walsh

Danielle Galligan, a Dublin-born actress, captured the attention of a global audience with her captivating performance as Nina Zenik in the hit Netflix fantasy series Shadow and Bone. Her portrayal of the witty and resilient Grisha tailor showcased her ability to handle both intense drama and sharp wit. Galligan’s television career also includes roles in the Irish crime drama KIN and the historical series The Great, proving her remarkable range across genres from fantasy to gritty realism and period satire.

Trained at The Lir Academy, Galligan has a strong foundation in theatre, which informs her detailed and physically expressive screen performances. Taking on the role of Claire Walsh, potentially the most responsible or troubled of the sisters, allows Galligan to delve into a character grounded in real-world drama. Moving from a high-stakes fantasy world to a intimate family saga highlights her versatility as an actress, and she is sure to bring a compelling intensity and emotional honesty to the Walsh family dynamic.

4: Máiréad Tyers as Helen Walsh

Máiréad Tyers is one of Ireland’s most exciting new talents, best known for her leading role as the fiery and ambitious young chef Emily in the Disney+ series The Kitchen. Her performance earned widespread praise for its charm, determination, and relatability. Tyers’s ability to carry a series with such a natural and engaging presence marked her as a star to watch. Her background includes training at the Bristol Old Vic Theatre School and a growing list of credits that demonstrate her comedic and dramatic chops.

As Helen Walsh, Tyers steps into an ensemble drama that will further showcase her ability to create a fully realized character. Her role in The Kitchen proved she can embody the spirit and anxieties of a young woman navigating her career and personal life, a theme that will likely resonate with her character in The Walsh Sisters. Tyers brings a vibrant energy and a refreshing authenticity to the screen, making her portrayal of Helen one of the most anticipated elements of the new series.

5: Caroline Menton as Rachel Walsh

Caroline Menton is a versatile Irish actress known for her work on stage and screen. She has appeared in popular Irish television series such as Can’t Cope, Won’t Cope and The South Westerlies, where she demonstrated a knack for portraying relatable, contemporary women. Menton’s strength lies in her naturalistic acting style, making her characters feel like real people you might know. Her experience in drama and comedy makes her a perfect fit for the world of The Walsh Sisters.

While perhaps less internationally known than some of her co-stars, Menton’s extensive work within the Irish industry brings a grounded reliability to the cast. Playing Rachel Walsh, she will be an integral part of the sisterly ensemble, likely portraying a character dealing with the specific pressures of career, relationships, or motherhood. Her performance will add a crucial layer of realism and heart to the family’s story, reflecting the everyday struggles and triumphs of modern Irish women.

6: Carrie Crowley as Mammy Walsh

Carrie Crowley, a native of County Wexford, is a beloved Irish presenter and actress. She first became a household name as the host of the Irish language children’s programme The Den. Crowley seamlessly transitioned to acting, delivering a stunning performance in the 1997 film The Boxer, directed by Jim Sheridan, where she starred alongside Daniel Day-Lewis. Her television work includes roles in Ballykissangel and more recently, as the formidable Sister Eileen in the critically acclaimed drama Smother.

Crowley brings a wealth of experience and a warm, commanding presence to the role of Mammy Walsh. As the matriarch trying to hold her family together, she is the emotional counterpoint to Aidan Quinn’s Jack. Crowley’s background in broadcasting gives her a natural ease in front of the camera, and her acting career has shown her depth in portraying strong, compassionate women. Her performance will undoubtedly be the nurturing heart of the series, embodying the complexities of a mother watching her daughters navigate adulthood.

7: Stefanie Preissner as Maggie Walsh

Stefanie Preissner is not just an actress but a celebrated writer and playwright, best known as the creator and star of the RTÉ comedy-drama Can’t Cope, Won’t Cope. The series, which was also adapted for BBC Three, was praised for its authentic and hilarious depiction of millennial life in Ireland. Preissner’s voice is distinct, sharp, and deeply relatable, capturing the anxieties and aspirations of her generation with honesty and humour.

Having Preissner, a multi-hyphenate talent, play Maggie Walsh is a fascinating prospect. It suggests that Maggie may be the sister with a particularly sharp or observational voice, perhaps a writer or artist herself. Preissner’s involvement, whether purely as an actress or also contributing to the writing, brings an guarantee of authenticity to the dialogue and character dynamics. Her performance will be layered with the intelligence and wit that defines all her work, making Maggie a potentially standout character.

8: Samuel Anderson as Aidan

Samuel Anderson, an English actor, is best known to international audiences for his charming role as Danny Pink, a companion to Peter Capaldi’s Twelfth Doctor in Doctor Who. His performance showcased his ability to blend everyday likability with emotional depth. Anderson has an extensive career in British television, with notable roles in shows like Gavin & Stacey and the comedy-drama Trollied, demonstrating his strong comedic timing.

Joining the cast as Aidan, likely a love interest or partner to one of the Walsh sisters, Anderson brings an affable and grounded energy. His character will serve as an outsider looking into the intense Walsh family dynamic, providing a fresh perspective. Anderson’s experience in both comedy and drama means he can easily navigate the show’s tonal shifts, from light-hearted family moments to more serious relational conflicts, making Aidan a believable and integral part of the sisters’ world.

9: Jay Duffy as Luke Costello

Jay Duffy is an emerging Irish actor who has quickly made a name for himself with standout roles. He gained significant attention for his performance as Tiernan in the hit RTÉ drama Smother, and more recently, he captivated audiences as the charming Tom in the ITVX romance The Couple Next Door. Duffy has a natural screen presence that blends charisma with a touch of vulnerability, making him ideal for roles involving complex relationships.

As Luke Costello, Duffy steps into another high-profile Irish production. His casting suggests that Luke will be a significant romantic figure in the series, potentially causing tension or offering support to one of the Walsh sisters. Duffy’s rising star power and proven ability to handle intense emotional scenes make him a perfect addition to the cast, and his chemistry with his co-stars will be crucial in building the romantic subplots of the show.

10: Debi Mazar as Chaquie

Debi Mazar, the acclaimed American actress, brings a dose of international flair to the cast. With a career launched by her iconic role as Maggie in Goodfellas (1990), Mazar became a fixture of the 90s scene with parts in My Cousin Vinny and as Shauna on the hit series Entourage. She is known for her sharp, New York-accented delivery and playing street-smart, no-nonsense characters. More recently, she starred in the comedy series Younger, showcasing her comedic talents.

The character of Chaquie, played by Mazar, is intriguing. She could be a colourful family friend, a relative from abroad, or a business associate who shakes things up for the Walsh sisters. Mazar’s presence indicates that Chaquie will be a bold, outspoken force who challenges the status quo. Her casting adds an exciting transatlantic dynamic to the series, promising fiery interactions and memorable moments.