Asterix and his friend Obelix tackle the leak of top secret Roman information with a strong dose of humour Thursday as the hugely-anticipated new opus of their adventures comes out in France and abroad.

After their last escapade in Scotland, the boisterous Gauls are back in their homeland in "Asterix and the Missing Scroll", teaming up with a reporter inspired by WikiLeaks founder Julian Assange to battle their favourite Roman foes.

The 36th edition in the hugely-successful Asterix comic book series, which features the adventures of an indomitable tribe of Gauls resisting Roman occupation, comes out around the world in Paris, London, Madrid, Montreal, Cape Town, with further releases planned in other countries at a later date.

Four million copies have been printed -- half in French and the rest in foreign languages.

Just hours before the global release, writer Jean-Yves Ferri told AFP he felt like he'd been "caught in a whirlwind."

"It's a more ambitious theme than the last book," he said, adding it took him a year-and-a-half to finish it.

On the side of the "goodies", "Confoundtheirpolitix" is introduced for the first time as a journalist who works for the "Condatum Echo".

Julius Caesar is on the verge of publishing his famous "Commentaries on the Gallic War" book and one of the chapters is devoted to his continual yet ever-unsuccessful quest to conquer the small village.

But that's not to the liking of his nasty, deceitful editor and agent Libellus Blockbustus, whose physical traits are strangely similar to those of French advertising magnate Jacques Seguela.

Caesar accepts to take out the offending chapter, but there is a leak and a scribe hands the bombshell to Confoundtheirpolitix, who tries to pass it on to Asterix. But will he succeed?

- Blue birds in forest -

The comic book abounds with winks and nods to modern technology, such as the blue birds in the forest reminiscent of the Twitter symbol.

The new adventures come two years after the Gallic duo re-emerged from an eight-year absence in "Asterix and the Picts", which took them to ancient Scotland for the first time and sold over 5.4 million copies in 15 countries and more than 20 languages and dialects.

The Asterix series -- created by illustrator Albert Uderzo and writer Rene Goscinny in 1959 -- is a bestseller in the comic book world, with some 365 million copies sold worldwide.

Over the years, the two characters from ancient Gaul have met Cleopatra, drunk tea with the English, taken part in the Olympic Games, and eaten countless roast boar.

With the help of a Druid-brewed magic potion that grants them superhuman strength, they have also taken great pleasure in beating up scores of Romans.

The series has been adapted into live-action films and is the inspiration for a popular theme park, Parc Asterix, outside Paris.

It has always been a hugely intimate affair and Uderzo, now 88, took over the writing after Goscinny died in 1977.

He quit drawing in 2011, and "Asterix and the Picts" was the first of the books to be written and illustrated by two entirely new people -- Ferri and illustrator Didier Conrad, who continued their collaboration for "Asterix and the Missing Scroll".