[1] She made her début in London’s Garrick Theatre playing a bridesmaid in J. M. Barrie’s The Wedding Guest (September 1900 – January 1901).
In 1902 she was back at the Savoy as Second Royal Page in Basil Hood and Edward German’s opera Merrie England, at the same time playing Norah in Aimée Daniell Beringer’s one-act play Holly Tree Inn at Terry's Theatre (April–May 1902).
[7] When the audience called for the author it was May who walked onto the stage to inform them that her friend Mr Barrie "was not in the house.
"[8] In April 1905 she played Child opposite Ellen Terry as Alice Grey and Irene Vanbrugh as Amy Grey in Barrie’s Alice Sit-by-the-Fire at the Duke of York’s, and then was Child in Barrie’s curtain raiser Pantaloon[3] with Gerald du Maurier in the title role at the Duke of York's (April–July 1905).
[9] In February 1906 she was again jokingly credited with Barrie as the co-author of the play when Barrie and producer Charles Frohman brought scenery and an all-child cast from the London theatre production for a special performance of Peter Pan for an unwell Michael Llewelyn Davies (with his brothers the inspiration for Barrie's characters Peter Pan, the Darling brothers, and the Lost Boys) in 'Michael’s Nursery' at Egerton House in Berkhamsted,[10] the family home of the Llewelyn Davies family.