MOST of us who live or work in London will have at some point reached for a copy of the A-Z. Over the years this trusty tome has been adapted and updated but has remained the Bible for getting around this ever growing city.
But how many of us know its origins, or that many believe it was created by a woman who hailed from East Dulwich in Southwark?
Well, all that could change thanks to a new musical, The A-Z of Mrs P, which opens appropriately at the Southwark Playhouse on Friday (21st).
Inspired by her autobiographies the show charts the story of how Bohemian artist Phyllis Pearsall left her husband in Venice in 1936 and came back to London.
Putting down her paints and picking up a drawing board, she started working for her father, map publisher Alexander Gross, and began to follow in her father's footsteps to map the city by walking every street.
Billed as a musical fable it stars Crystal Palace actress and comedian Isy Suttie, perhaps best known for her her role as Dobby, the nerdy girlfriend on Channel 4's Peep Show, as Mrs P.
Taking a break from rehearsals the award winning 34-year-old says she has enjoyed not only doing a musical but also finding out more about Mrs P.
"I'd never really heard of her, didn't know her back story and so this has been a fantastic project to be involved in," she says warmly.
"I've been reading her autobiography while we rehearse. She had a fascinating if somewhat sad life as her father was quite cruel towards her at times.
"But she was very stoical and strong and I think that's what attracted me towards her and the part. She was cool, adventurous, witty and flirtatious at times but she went through an awful lot, including having to cope with rejection from her parents.
"She also embroidered a lot of things so no one really knows if she did actually walk every London street and was responsible for the A-Z but I'd like to think she was as she sounds like a great lady."
And she admits the A-Z has come in quite handy since her recent move to Crystal Palace.
"It's nice to find out about the lady whose book I use all the time," she chuckles.
"Crystal Palace is great and it's lovely being here and getting to know it," she adds. "It's poles apart from Elephant & Castle where I had been living. It's green and very villagey whereas Elephant is very gritty.
"But I love South London - I've lived all over the place from Peckham, East Dulwich and Camberwell. It's got a lovely vibe, lots of open spaces and it's so easy to get to the Southwark Playhouse for this show which is obviously very handy!"
As well as the ideal location, the production appealed to Isy because of its musical element.
Indeed, Isy actually started out as a composer after graduating from the Guildford School of Acting.
Since then she has gone on to do several highly successful solo Edinburgh shows, has appeared on TV, film and stage, has her own BBC Radio 4 radio series, Isy Suttie's Love Letters and along the way been nominated for numerous awards.
"I still do composing and I've been writing songs since I was 11," she says warmly. "My radio show is a mix of storytelling and music and I did musical youth theatre at school but this is the first proper musical I've done.
"After graduation I got obsessed with stand up but then ended up doing more TV. I haven't done much theatre - in fact I'd not done much since drama school so I was keen to do this. It doesn't feel too much of a jump. It's a great show with the most beautiful music so it's very exciting.
"Also, it has a four-week run which is really nice as it's quite lonely doing stand up sometimes - it's nice to actually be able to get to know people doing a job like this and go to lunch with them!" she laughs.
But despite her success and not inconsiderable achievements, Isy remains down to earth and modest.
"I've done some amazing things and winning the Sony Award was very cool," she admits chuckling.
"I just try and do my best but really I can't believe I get paid to do this - I have to pinch myself sometimes. I'm very lucky!"
The A-Z of Mrs P is on at the Southwark Playhouse, Newington Causeway from Friday, February 21 until Saturday, March 29.
Tickets cost £22, £18 concessions. Call the box office on 020 7407 0234.