She went on to be a regular in Dangerfield (1996), Cardiac Arrest (1996), Four Fathers (1999) and Home Farm Twins (1999), and also appeared in Crocodile Shoes (1994), Peak Practice (2000), Down to Earth (2001), Cold Feet (2001), I'm Alan Partridge (2002), Holby City (2003), Silent Witness (2005), New Tricks (2011), The Bill and Casualty many times (1996–2012), Being Human (2010), Law & Order: UK (2010), Midsomer Murders (2021), The Killing Kind (2023) and Ridley (2022) with Adrian Dunbar, among others.
May's legal thriller Lawless, starring Suranne Jones, Lindsay Duncan and Jonathan Cake, was piloted in 2012 on Sky Living.
She wrote for two series of Living The Dream for Sky Comedy, starring Philip Glenister and Lesley Sharp (2017–2019).
May co-founded the award-winning new writing theatre company Plain Clothes Productions, commissioning, producing and directing for the company, which toured the UK, and played the Traverse, the Bush Theatre, the Young Vic, and Battersea Arts Centre.
In 2019 she associate directed Brigit Forsyth in Killing Time, by Zoe Mills, at 59E59 Theaters, off-Broadway, New York.