Hurrah! Spot on Niki!!
Agatha Christie wrote several "non-crime" novels under the pen name Mary Westmacott.
Interesting related fact No 1 (or not, as the case may be!) - my maiden name is Westmacott so I've always remembered this little bit of trivia as it's such an unusual name. I'd love to know why she chose it for a pen name.
Interesting related fact No 2 (or even less so, probably!) - there is a Labrador breeder in Northumberland whose kennel name is Westmacott and he told me he named his kennels after the street he used to live on ("Westmacott Street"), which I then found out was named after Percy Westmacott who was a big name in the Vickers factory which was a big employer in the area - and he was my great great Uncle!!!
Over to you, Niki!