Kat Stewart
Katherine Louise Stewart, known professionally as Kat Stewart, is an Australian actress who has made numerous appearances in television series, movies and on-stage.
Early life
Kat Stewart is the daughter of Tony and Kitty Stewart and was born and raised in Bairnsdale, Victoria. When she was eight years old she, her parents and two older brothers lived and travelled in Europe for a year and Stewart said that time "opened my eyes to the world and gave me a lot of confidence." Stewart began acting in primary school and remembers: "Since Year 2 I had been getting a thrill out of doing school drama. I was on the quiet side, but I felt light in my bones when I was onstage. At university I studied marketing and arts, and joined the theatre society, which quickly became my passion. After graduation, I worked in publicity, but I couldn't shake my love of acting, so I enrolled at the National Theatre, hoping I'd outgrow it. Now I understand you need to do what you love to be happy." Stewart decided to leave PR behind to pursue acting full-time and recalled: "After I finished drama school, I had a couple of acting gigs straightaway, but then I was unemployed fairly consistently over a couple of years. I don't take anything for granted now though, so it wasn't such a bad thing. But I wouldn't want to go back there if I can avoid it."Career
Television
Kat Stewart is best known for her role as Roberta Williams in the first series of the Channel 9 TV production Underbelly and as Billie Proudman in the popular comedy/drama, Offspring on Network Ten.It was her award-winning performance in Underbelly in 2008 that first made Stewart a household name. The portrayal of Roberta Williams drew praise from critics including Marcus Casey of The Daily Telegraph, who described it as 'one of the most compelling performances by an Australian actress in memory.' Casey expanded that it was 'a brutally brave, ugly and compelling performance...She held nothing back, and was an emotional but controlled and screeching tornado who dominated the screen whenever the camera peered her way.' The authenticity of Stewart's performance was praised by Michael Lallo in The Age, who said: "By any measure, it's the role of a lifetime. Stewart has ensured it's the standout performance of the series. Despite quality performances by all, critics say she owns every frame she's in. It's not that she delivers a superb depiction of a suburban gangster moll; it's that you really believe she is a suburban gangster moll." Although her performance was popular with critics and audiences, the real life Roberta was not a fan but Stewart was sympathetic, "Obviously, I would have preferred her to like it," she said. "But I can't control that. And if someone was playing me, I couldn't imagine I'd be happy…I have a lot of empathy for Roberta and what she's been through". Stewart acknowledges the show was a key moment in her career, "Underbelly opened a lot of doors and gave me access to better opportunities and more opportunities. I am very grateful for it".
Despite her positive experience in Underbelly, Stewart chose not to reprise the role in Fat Tony & Co in 2014. Stewart told David Knox of 'TV Tonight': "..Seven years ago when I did it we didn’t know much about Roberta Williams. So I did as much research as I could...Now we know how she walks and talks and so much more about her...I don’t like turning down work. It goes against every actor instinct. But it just didn’t feel right".
After the success of Underbelly Stewart next appeared in the critically acclaimed relationship drama, Tangle on Showcase. In the series Stewart played the loveable but flawed, Nat Manning alongside Justine Clarke, Ben Mendelsohn, Matt Day and Catherine McClements. Showing she has long been adroit at both drama and comedy, in 2009 Stewart appeared in the Andrew Denton produced, advertising industry satire :30 Seconds on Comedy Channel.
Stewart won many new fans in her role as Billie Proudman on Offspring, as part of an ensemble cast led by Asher Keddie and including John Waters, Eddie Perfect, Deborah Mailman, Richard Davies, Garry McDonald, Lachy Hulme and Linda Cropper. One of the show's strengths is the dynamic relationship between the sisters Billie and Nina Proudman. Both actresses have spoken of their admiration for each other, with Stewart saying "I've admired Asher ever since Love My Way. She is an actress of extraordinary ability and depth. We have a lovely shorthand and support for each other on set, not unlike Nina and Billie. There's a trust there that allows real spontaneity and joy." Keddie spoke of Stewart, saying "It's exhilarating to perform with her; I feel genuinely excited by it. That's a great feeling to have as an actor - when you really want to be working opposite someone and with someone. It doesn't get much more rewarding than that." Stewart admits to being fond of her character, Billie, despite some heartaches, "I’m really fond of her, though she’s really frustrating sometimes. Though she cheated on Mick , it’s my job to see the world through her eyes. You see what happened in the lead-up and it was the ultimate act of self-destruction. It broke my heart." Offspring aired for 5 seasons from 2010 to 14 before returning to TV screens for a sixth season in 2016. With production of the new series underway Stewart spoke to Colin Vickery of News Corp, "I really didn’t think it would happen", Stewart said. "It was the best experience I’ve had in a show. You form such deep relationships with the people and also the characters. I feel really confident we’ll be able to deliver something great. I don’t think we’re going to coast on some sort of legacy. We’re really aware of that and all want it to be as fantastic and awesome as it can be. To get to walk around in Billie’s shoes again is fantastic". The seventh season of the show, including Stewart and other key cast members, screened in 2017. Writing in 'The Daily Telegraph', Colin Vickery reflected on season 7 with "this year...Billie, played by Kat Stewart, has had to endure a heartbreaking split with husband Mick. Billie's rollercoaster life has showcased Stewart's comedic and dramatic talents like never before. No wonder many critics believe she is the best actor on Australian television."
Stewart teamed with Shaun Micallef in the murder mystery drama/comedy, Mr & Mrs Murder on Network Ten in 2013. The pair played Charlie and Nicola Buchanan, a husband and wife duo of industrial cleaners with an amateur interest in solving crimes. The two previously worked together on the satirical SBS newscast show Newstopia and both have spoken positively of their on-screen chemistry and rapport with Micallef saying "I wouldn't have considered doing this if Kat wasn't involved." Stewart also shared an Associate Producer credit on the show.
From 2019 to 2023 Stewart appeared in the Network Ten and Paramount+ housemates' drama Five Bedrooms co-starring with Stephen Peacocke, Hugh Sheridan, Kate Jenkinson, Doris Younane, Katie Robinson, Johnny Carr and Roy Joseph. In an interview with Debi Enker of The Sydney Morning Herald, Stewart said of her character in Five Bedrooms, "Liz is brave, but also fragile. I find her heart-breaking, but she can come off as a bit cold. I don’t think people will necessarily warm to her quickly. She’s complicated and I think that the older we get and the more that we’ve marched in the world with our armour, we don’t throw it off in a hurry. Liz’s got a lot of armour". Reflecting on the show itself Stewart commented, "It’s a challenge to make TV that’s fresh and of the time, because we’re competing with such brilliant overseas content. Going off the intelligence of the scripts, the heart and the humility and the humour, I feel like this is very much of the time. It feels fresh to me: it’s something I wanted to be a part of and something I would want to watch". In a review in the The Sydney Morning Herald in 2022 Melinda Houston concluded: "Not to mince words, Five Bedrooms is one of the most criminally underrated shows on television right now....Fresh, relevant, smart, equal parts funny and heartbreaking, it’s an absolute delight."
2020 saw Kat Stewart appear as one of the featured celebrities in the 11th season of the Australian version of the television documentary reality genealogy series Who Do You Think You Are? on SBS.
In 2023 Stewart appeared in One Night on Paramount+, alongside a cast including Jodie Whittaker, Nicole da Silva and Yael Stone. In 2025 Stewart featured in a supporting role in the second series of the crime drama Black Snow starring Travis Fimmel on Stan.
Stewart's other TV credits include guest appearances in the Nazeem Hussain sketch comedy series Orange Is the New Brown in 2018, True Story with Hamish & Andy on the Nine Network in 2017, No Activity on Stan in 2015, It's a Date and Jack Irish: Dead Point in 2014, Camp on America's NBC in 2013, Miss Fisher's Murder Mysteries in 2012, various roles in Newstopia on SBS in 2007–08, the BBC2/UKTV comedy series Supernova, as well as recurring roles on City Homicide, Kick, and Last Man Standing. Earlier in her career Stewart had guest roles on Blue Heelers, Stingers, CrashBurn, Something in the Air, The Secret Life of Us, and Fergus McPhail. In 2015, Stewart appeared with close friend and mentor Ailsa Piper in the contemporary interview program 'The Truth About Us' on Foxtel's Bio. channel.
Stage
Kat Stewart has won acclaim on-stage in a range of dramatic and comedic roles. As an ensemble member of Red Stitch Actors Theatre from 2002 to 2012 Stewart appeared in over a dozen plays for the company including The Little Dog Laughed, The Shape of Things, Rabbit Hole, Bug, Dirty Butterfly, Play About the Baby and Loyal Women. In 2010 she appeared in the part of Tekla in an update of August Strindberg's Creditors.In 2014, Stewart featured in Melbourne Theatre Company's production of The Speechmaker. The political satire was the first play from Australian filmmakers Working Dog Productions and the writing trio of Santo Cilauro, Tom Gleisner and Rob Sitch. When asked about the production and returning to the stage after a four-year break Stewart said "I’ve always wanted to work with Working Dog. The script is engaging, smart, alarming and funny. I used to do six or seven plays a year. But I think you can lose your nerve if you leave it too long." The play also featured Stewart's Offspring cast-mates, Lachy Hulme and Jane Harber. Stewart had previously worked with MTC on productions such as Festen in 2006 and 2008's Frost/Nixon. In August 2016 she had a starring role on stage in the MTC production of Ayad Akhtar's 2013 Pulitzer Prize winning play, Disgraced, earning critical praise in the part of Emily.
Stewart appeared in the 2019 Melbourne Theatre Company production of the Simon Stephens' penned romantic comedy, Heisenberg. The production was directed by Tom Healey and co-stars Peter Kowitz. Stewart earned praise in the role of Georgie with Andrew Fuhrmann of the Herald Sun saying, "This new MTC production is elegantly done, with a slow, almost meditative rhythm. And it features a wonderfully engrossing performance by Offspring star Kat Stewart." He further summarised, "... really, the best reason to see this production is Stewart's finely modulated performance. Her Georgie is both utterly untrustworthy and deeply sympathetic."
In 2022, Stewart returned to the stage in the Melbourne Theatre Company production of Joshua Harmon's education satire Admissions. The production was directed by Gary Abrahams and co-starred William McKenna, Heidi Arena, Simon Maiden and Deidre Rubenstein. Cameron Woodhead of The Age described Stewart's performance as '...the glossiest possible portrayal of liberal officiousness and the cynical abyss her wokeness teeters into when the chips are down.'
Stewart starred as Martha in three productions of Who's Afraid of Virginia Woolf?, alongside the same cast including real-life partner, David Whiteley, as well as Harvey Zielinski and Emily Goddard. In 2023 and 2024 the quartet appeared in Red Stitch Actors Theatre productions, including a season at the Comedy Theatre in Melbourne, and followed by a Sydney Theatre Company run at the Roslyn Packer Theatre in late 2025. John Shand of the Sydney Morning Herald and The Age put the Sydney production in his top 5 of 2025, saying of Stewart "This is a performance that will throb in the memory bank long after age has pilfered most of them. Stewart’s light-switch mood changes are scary enough; her Martha’s rage is cyclonic, her intellect formidable, her capacity for alcohol bottomless and the terror on her face near the end heartbreaking."