Roo has always been curious. Whether she is following an interesting scent, making a new friend or finding herself somewhere she probably shouldn’t be, she has a habit of turning an ordinary day into an adventure.

But for Roo and the Secret of Barnacle Bay, I wanted to take her much farther from home.

Barnacle Bay is a place of cobbled streets, bobbing fishing boats, towering cliffs and salty sea air. It is the sort of seaside town that seems warm and welcoming at first glance—but look a little closer and there are stories tucked into every corner.

And perhaps one or two secrets too.

A bigger adventure for Roo

The Roo’s Garden picture books are set in a small, familiar world filled with woodland animals, changing seasons and gentle lessons. Roo’s Big Adventures gives me room to stretch her legs—and the story—much further.

In Roo and the Secret of Barnacle Bay, Roo travels to the coast with Margo and Jerry, expecting a holiday filled with walks, sand and seaside snacks. She has never seen the sea before and isn’t entirely sure what to make of it. It moves, it roars, it smells peculiar and, rather inconveniently, it refuses to stay in one place.

Luckily, Roo meets Dylan, an older Labrador who knows Barnacle Bay well. He becomes her reassuring guide and loyal companion as a simple holiday begins to turn into something much more mysterious.

I wanted the setting to feel almost like another character in the story.

Barnacle Bay needed cheerful seaside details—bright shopfronts, ice cream, boats in the harbour and gulls overhead—but also a sense that the past was never very far away. Its old lighthouse, weathered harbour walls, clifftop paths and hidden coves all hold traces of the people who lived there before.

The mystery begins when an old piece of parchment is discovered inside a book. It contains a riddle connected to a local legend and a secret that may have been waiting for three hundred years.

That gave me the thread I needed to lead Roo and her friends through the bay. Each clue reveals something new about the place while drawing them closer to the truth.

Of course, humans tend to rely on words, maps and sensible explanations. Roo has another advantage entirely: her nose.

She notices smells that do not belong, follows trails that others miss and has a determined way of making herself understood when something matters. Roo may not be able to read the riddle, but that certainly doesn’t mean she cannot help solve it.

Mystery without losing the warmth

Although this is a mystery adventure, I still wanted it to feel unmistakably like a Roo story.

There is suspense, but it is gentle enough for readers aged six to nine. There are puzzles and moments of danger, but also friendship, humour and plenty of small observations from Roo’s particular doggy point of view.

She understands the world largely through smells—and food is never far from her thoughts. A room can contain an ancient clue, a fascinating local legend and several excited humans, but Roo will still notice if somebody has dropped a crumb of toast.

That balance was important to me. I wanted young readers to feel the thrill of a real mystery while always having Roo’s warmth and humour beside them.

At its heart, the story is also about courage. Roo is excited by the adventure, but she is not fearless. The sea is new and sometimes frightening, and there are moments when she needs Dylan’s calm presence. Being brave does not mean never feeling worried. Sometimes it means taking the next step with a good friend beside you.

Painting the seaside

Illustrating Barnacle Bay gave me the chance to create a very different visual world from Roo’s Garden.

Instead of woodland paths and cosy burrows, I could paint wide skies, moonlit water, colourful harbour buildings and dark rocks shining beneath the lighthouse beam. The ink-and-watercolour illustrations helped me capture both sides of the bay: its cheerful holiday atmosphere and the older, more mysterious world hidden underneath.

One of the challenges was keeping the locations clear and memorable as the mystery developed. The harbour, shops, cliffs, lighthouse and shoreline are not simply backgrounds; they all play a part in the story. I wanted children to feel that they were exploring Barnacle Bay alongside Roo, noticing clues and wondering what might be around the next corner.

A story about the treasures we keep

I won’t reveal exactly what Roo discovers. That would spoil the mystery.

But Roo and the Secret of Barnacle Bay asks a question that sits beneath the riddles, legends and hidden places: what makes something a treasure?

Is it its value, its age or the story it carries? And when part of the past is rediscovered, does it belong to the person who finds it—or to everybody whose history it represents?

For Roo, the adventure begins with a holiday and an unfamiliar sea. It becomes a journey filled with friendship, courage and discovery—and proof that even the smallest member of an expedition can notice the most important clue.

After all, Barnacle Bay has kept its secrets for a very long time.

It may simply have been waiting for the right dog.

Roo and the Secret of Barnacle Bay is a richly illustrated mystery adventure for children aged 6–9, ideal for shared reading and newly independent readers. It is part of the Roo’s Big Adventures series.