The Opus Dictum

A Vatican Secret Archive Thriller

Two clandestine syndicates want control over the Church’s power … and the tools to do it are hiding deep in the Vatican Secret Archives. But first they have to deal with a meddling priest who could ruin their plans.

Father Michael Dominic is intrigued when a long-lost briefcase is discovered in the Vatican Secret Archives. Inside, he finds incriminating documents, a special key, and a computer disk filled with codes, which together unlock a piece of the Catholic institution’s troubled past. Suspicious they could influence a special conclave to elect a new pope, Dominic must discover what the documents reveal before it’s too late.

But the two menacing institutions close in on Dominic, intent on taking the key and cipher for their own sinister ends. Father Michael, his young assistant, and a feisty young nun have to work together to decode the information before anyone else. Can they solve the puzzle in time, or will their enemies obstruct centuries of Church history?

If you loved The Magdalene Chronicles, or books by Daniel Silva or James Rollins, you’ll devour this new, blistering thriller! Find out why McAvoy’s fans say, “I couldn’t stop turning the pages!”

Published January 1, 2022

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Rated “Must Read” 🏆 ⭐️⭐️⭐️⭐️⭐️

“Always eager to read the work of Gary McAvoy, I rushed to begin the latest featuring Father Michael Dominic, which did not disappoint. Exploring another angle of Vatican-based politics and sinister goings-on, McAvoy takes readers through a historical event and provides strong modern action to support it. In this case, all relates to a more recent event, where a mysterious briefcase finds itself in the Vatican Archives. What it contains could not only reveal the existence of a powerful group thought defunct, but also change the path of the Catholic Church forever. It will be up to a handful of dedicated individuals to stop this before it’s too late. Another winner by Gary McAvoy that will have those who love a good thriller on the edge of their seats.

I have followed Gary McAvoy on this journey since its inception and never found myself straying. The themes that emerge are on point and I am regularly pulled in by the approach of his plot lines. The Vatican is a complex and multi-layered organisation, as is the Catholic Church in general. McAvoy finds ways, through history and artifacts, to bring the story to life and create thrilling adventures for all to enjoy. His characters grow exponentially throughout and the stories connect well together. This is a series that gains momentum with each novel and never seems to lose its way.

Father Michael Dominic continues to impress as the protagonist of the series. His backstory is a little complicated, as series fans will know well, but it is matched by some of the awkwardness he hides in the present that keeps it all highly exciting. A devout Catholic who loves working in the Archives, Dominic finds mysteries fuel him and will stop at nothing to uncover the truth before him. While he may not hunt out danger, there are those around him who seem to attract it, creating an adventurous journey through each of the novels in this series. I am eager to see, with some of the revelations made in this book, how things will change for Father Dominic moving forward and whether there will be a significant shift in his role.

The key to a strong thriller novel is whether the reader can feel themselves begin a part of the action, rather than a passive bystander. Gary McAvoy creates an electric buzz around his stories and puts the reader right in the middle of everything that is going on. His narrative builds with each passing chapter, developing more mysteries and curiosities, while the plot twists repeatedly to keep anyone from knowing exactly what will happen. Intertwining modern events with historical goings-on makes for an explosive story that could go one of many directions. Strong characters, particularly those who reappear and build on their past developments, help create an emotional connection for the reader, as they are swept up in everything that is taking place. While McAvoy packed this book with history and highly descriptive settings, I know this is not the end. While I will have to patiently wait for the next instalment, it will surely be well worth it to see how things continue to play out for all involved.

Kudos, Mr. McAvoy, for another stunning story. You never cease to amaze me with your writing.”
— MATT PECHEY, Reedsy Discovery

McAvoy has given us another great adventure into the world of intrigue around the struggle for power in the Vatican. I like that this adventure centers around an ultra conservative right wing group bent on gaining control of the Roman Catholic Church. It is really believable after the political events we have seen in the U.S. and other countries in the last several years.

Many of the characters in this novel we have seen in previous books by McAvoy. This novel does read well on its own, however. Father Dominic and those on his side desire to have the Catholic Church exist at its best. They come against powerful forces, some within the Church itself.

I like to learn something when I read a novel. In this one, there is much about the operation of the Vatican and particularly about a papal conclave. I also learned about steganography. In the novel, a text document was hidden in a photograph. And that was in the 1980s.

I can tell McAvoy has done an immense amount of research to make this novel as accurate as possible. He says in his Author’s Note that he wants readers to feel like they are actually there as they read through the story. I certainly did. I really like his precise descriptions of the Vatican and other aspects, such as restaurants, foods, gardens, etc. McAvoy also tells readers the historical facts upon which he built his novel. He is an intelligent writer and a stickler for details, from weapons to Vatican finances, and that makes reading his novels both entertaining and informative.” — JOAN NIENHUIS, Professional Book Reviewer

The Opus Dictum is an intense, thrilling, fast-paced novel containing plenty of intrigue, action, suspense and heightened danger. The author once again seamlessly blends well-researched historical facts into a pulse-pounding new book with endearing, undaunted, believable protagonists and ruthless villains. Highly recommended for those readers who enjoy a stimulating, impeccably researched, well-plotted adventure with plenty of action.” — CAROLYN WALSH, Canada

“As in the previous four Father Dominic books, The Opus Dictum was a thrilling ride through the inner workings of Vatican City and the occupants of the Vatican itself. I almost feel the need to buckle in before picking up one these books! The historical detail in the settings and facts, the characters and their relationships and dialogue and the suspense of the chase as the characters try to save, recover or find the antiquities of the Church all come together beautifully to create a non-stop page turning experience unlike I get with most fiction I read. I believe what draws me most to Gary McAvoy and his work is he’s not trying to push a narrative down my throat, he’s accepting of all ideas, and it’s probably the first thing I noticed when I began reading his books over a year ago. When I’m asked now what to read by someone who doesn’t have a particular genre in mind and is looking for that all around great read filled with excitement and intrigue, the first words out of my mouth are always, ‘Gary McAvoy and his Magdalene Chronicles series!* — KYMM CUMMINS, California

“I’m a big fan of Gary McAvoy as a writer; his style is tremendous: intelligent, articulate, conscientious, hardworking and incredibly knowledgeable – and that is just to start. He possesses that rare thing which separates a wonderful writer from a wonderful author: a meticulous researcher, whose books are intended for an equally intelligent, discerning reader, who appreciates the better things.

I believe this is the fourth I have read in this series, with its familiar characters, clearly now much beloved by their creator, and I was fortunate enough to read them in exactly the order they should be; this would certainly be my first piece of advice for any reader looking to pick up this book as a standalone, or dip into Gary’s books on a whim: the series must be read in order.

I really like Gary’s action sequences and I look forward to them, anticipating them almost as a trademark of his work, with their Clancy-esque authenticity of special operative combat techniques. As always, he shows discipline not to overdo the action, by way of keeping his subject matter and genre firmly within the intellectual arena. His attention to detail is formidable in every single area. He makes his research appear innate and effortless, but if there were any doubt how much graft he puts into his writing, he includes a fascinating glossary of the sheer amount of research work involved. If you haven’t read Gary McAvoy, I strongly recommend it; he is a rare writer indeed.” — MATT McAVOY, United Kingdom (no relation to author)