Kacey Ainsworth

Kacey Ainsworth (born 19 October 1968) is an English actress, known for her roles as Little Mo in the BBC soap opera EastEnders (2000–2006) and Cathy Keating in the ITV drama series Grantchester (2014–present).

Early life Upon finishing senior school, Ainsworth secured a job at the advertising firm Saatchi & Saatchi. She returned to acting in the 1990s, appearing in various guest parts on television and as Miss Fitzherbert in Mike Leigh's Oscar-nominated musical drama Topsy-Turvy (1999), before joining the cast of the BBC soap opera EastEnders, where she played Little Mo—a member of the Slater family—between September 2000 and May 2006. The storyline in which her character endured a prolonged campaign of abuse at the hands of her husband has since been recognised as one of the most powerful depictions of domestic violence in British television history, with Ainsworth commenting that the role often left her physically and emotionally drained.

Since leaving EastEnders, Ainsworth has appeared in a string of guest roles on series such as Hotel Babylon, Midsomer Murders, Casualty, Doctors, Call the Midwife, Moving On, Shakespeare & Hathaway, and The Madame Blanc Mysteries. She also starred as Inspector Jenny Black in the BBC's HolbyBlue (2007–2008), appeared in the recurring role of Miss Gullet on the debut season of CBBC's The Worst Witch (2017), and played a supporting role in the acclaimed film Lynn + Lucy (2019). She has co-starred as Cathy Keating in the ITV detective drama Grantchester since 2014, writing an episode for its ninth season in 2025.

On stage, Ainsworth starred in touring productions of The Taming of the Shrew (1998), Calendar Girls (2011–2012), and Steel Magnolias (2012). In 2019, her portrayal of Mrs. Lovett in Stephen Sondheim's Sweeney Todd—at the Everyman Theatre—drew praise, with Michael Billington of The Guardian calling it an "outstanding performance".

Filmography Year Title Role Notes 1995 Peak Practice Julia Episode: "Walking Away" Under the Moon Sarah Television film 1996 A Touch of Frost Carole Nash Episode: "The Things We Do for Love" Accused Rosie Murray Episode: "Billy" The Moonstone Drusilla Clack Television film 1996–1997 The Bill Paula Sheriton / Gail Painter 2 episodes 1997 Cone Zone Loretta 4 episodes The Beggar Bride Tina Main cast; 2 episodes 1998 Touch and Go Val Television film Where the Heart Is Tracey Episode: "Love" 1999 Topsy-Turvy Miss Dorothea Fitzherbert Feature film 2000 Happy Birthday Shakespeare Rita Television film Safe as Houses Jan Television film 2000–2006 EastEnders Little Mo Mitchell Series regular; 552 episodes 2001 Girl from Rio Sales Assistant Feature film 2007 Hotel Babylon Maria Henson Episode #2.1 2007–2008 HolbyBlue Inspector Jenny Black Main cast; 14 episodes 2010 Rock & Chips Edna Episode: "Five Gold Rings" 2011 M.I. High Margaret Fontana Episode: "Bully Elliot" Tracy Beaker Returns Xanthe Episode: "Grandad" Midsomer Murders Nikki Rowntree Episode: "Echos of the Dead" 2013 The Wright Way Valerie Wright Main cast; 5 episodes 2014 Casualty DS Annie Reardon Episode: "Valves to Vagrants" Doctors Ruby Slade Episode: "Snowbabies" Call the Midwife Nancy Episode: "Christmas Special" 2014–present Grantchester Cathy Keating Main cast; 65 episodes 2016 Agatha Raisin Francie Juddle Episode: "Witch of Wyckhadden" 2017 The Worst Witch Miss Gullet Recurring; 12 episodes 2017–2018 Loose Women Self/Guest Panellist 3 episodes 2018 We the Kings Susan Feature film 2019 Lynn + Lucy Caroline Feature film 2020 Moving On Vicky Episode: "Second Sight" Then & Now Claire 3 episodes; also co-writer 2021 The Battersea Poltergeist Lily Chibbett (voice) Podcast; 3 episodes Torchwood Jill Kerr (voice) Podcast; episode: "The Five People You Kill in Middlesbrough" Sliced Denise Episode: "Mad Innit?" The Mallorca Files Linda Ball Episode: "The Blue Feather" 2023 Doctor Who: The Sixth Doctor Adventures Beryl (voice) Podcast; episode: "Girl in a Bubble" 2024 Whitstable Pearl Cassie Episode: "Death, the Devil and the Fool" 2025 Shakespeare & Hathaway: Private Investigators Jane Folle Episode: "A Rose by Any Other Name" The Madame Blanc Mysteries Aurielle Alfonse Episode: "Christmas Special"

Theatre Year Film Role Notes 1978–1981 Annie Tessie Victoria Palace Theatre 1995 Pale Horse Lucy Royal Court Theatre 1996 Serving It Up Teresa Bush Theatre 1997 Attempts on Her Life Girl Royal Court Theatre 1998 The Taming of the Shrew Kate UK tour 1999 Sleep With Me Lorraine Royal National Theatre 2006 The Exonerated Guest Lead Riverside Studios 2009 Carrie's War Auntie Lou Apollo Theatre 2011–2012 Calendar Girls Miss November UK tour 2012 Steel Magnolias Annelle UK tour 2013 Laughton Elsa Lanchester Stephen Joseph Theatre 2015 Feed the Beast Sally Birmingham Repertory Theatre 2018 Holes Warden Nottingham Playhouse 2019 Sweeney Todd Mrs. Lovett Everyman Theatre 2022 Lava Vicky Soho Theatre 2023 Little Women Marmee HOME 2024 Leaves of Glass Liz Park Theatre Jab Anne Finborough Theatre

Awards British Soap Awards – Best Actress (Winner, 2002; 2003) National Television Awards – Most Popular Actress (Winner, 2002) Inside Soap Awards – Best Actress (Winner, 2002) TV Choice Awards – Best Soap Actress (Winner, 2002)