The plot of What Friends Do Best was originally devised as a sequel to another of my picture books Bringing Down the Moon. The main character of that book was a mole, but the sequel was to be centred on Mole's friend, squirrel. The story was about how Squirrel wanted to prepare a big meal for all her friends. She starts off determined to do everything herself, declining all offers of assistance. But when things go wrong, she learns that she cannot succeed without the help of her friends.
However, the editor I was working with was not happy with the story, so I tried to take a fresh look at it.
Around this time I saw a TV documentary series called Plane Crazy, made by the US writer and broadcaster Bob Cringely. In the series Bob, an experienced amateur plane builder, sets out to design, build and fly an airplane in just 30 days. You don't have to be an aircraft designer to appreciate what a hugely ambitious project this was and it wasn't long before Bob found himself way behind schedule and working late into the night in an attempt to make up for lost time. As Bob becomes increasingly exhausted and depressed his girlfriend and even the camera crew offer to help out, but Bob insists on soldiering on alone. However, as the deadline draws near, it becomes clear that Bob has no hope of completing the task alone and he eventually accepts assistance.
The idea that it's OK to let your friends help seemed to come as a great revelation to Bob and this part of the programme struck a resounding chord with me. The situation in the documentary seemed to relate so well to what I wanted to write about in my story that I abandoned the idea of using the story as a sequel* and reworked the plot with a new set of characters - a cat, a dog and a mouse - and made it about constructing a vehicle instead of preparing a meal.
The vehicle that the three friends build is deliberately not mentioned in the text, as I wanted to keep readers guessing what it was right up to the end**. However there are some clues in Nathan Reed's illustrations. Some of the clues are straightforward, like bits of the vehicle that are seen lying around in Winston's workshop. Others are more tricky – a few boffins may recognise that the formulae jotted on the back of the drawing that Winston show his friends are for calculating aerial trajectories and that the distances written across the top of the same drawing are big enough to be interplanetary.
* I have since written two sequels to "Bringing Down the Moon" - "No Place Like Home" and "A Diamond in the Snow" - both of which are due to be published.
** I wrote this before the paperback edition came out. The paperback has the completed vehicle on the cover, so it's identity is less of a mystery.
The plot of What Friends Do Best was originally devised as a sequel to another of my picture books 
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