By Caroline Wyatt
BBC correspondent in Paris
France, the home of comic book hero Asterix, is now falling prey to a new and foreign art form - Japanese manga comics.
Asterix regularly beats off the Roman invasion - but what about the Japanese?
Manga comics - only introduced in 1989 - now make up 30% of the country's comic book market.
Their appeal has grown massively by word of mouth and the appeal they have for young people.
"With manga we suddenly discovered there are thousands of stories of artists that we didn't know, and that's extraordinary," Manga expert Julien Bastide, of Anime Land magazine, told BBC World Service's The World Today programme.
"You open the door and there is all this for 100 years, so that's why I am interested in manga, because we don't know anything about manga yet."
France has a long history of comic book stories, with Asterix probably the most famous. Tintin, from neighbouring Belgium, is also hugely popular.
But the Japanese invasion of comic heroes and superheroines began in 1989 and they've been gaining ground ever since, especially with French teenagers.
Though the dialogue is mostly translated into French, real connoisseurs know that the words "boin boin" signifies the bouncing of a character's breasts, while "bashi bashi" is the sound of someone being hit on the head.
Julien Bastide admits that the allure of manga is not something French parents really understand: "It's about a guy who is 15 like you, and fighting against whatever, and saving the earth and getting the girl and something like that.
"So when you are teenager what fascinates you? Violence, and also sex."
At one specialist comic shop, the latest delivery of manga has just come in and the customers are already queuing outside.
Daniel, who is sticking the prices on each comic, says manga's attraction is simple.
"The fascination is maybe French young kids more curious about Japan - it's exotic and when you are young you read things that grown up do not read," he explained.
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"They want something that is from another country that is cool, so maybe that is part of the attraction."
For the customers - aged anything from 14 to 40 - a large part of the attraction is price.
The black and white manga books, printed on cheap paper, are half the price of their French equivalents.
Manga fans can be found in the least likely places in France. The Martin family, just outside Paris, take their enthusiasm to a different level - so keen are they on manga that they even dress up as their favourite characters.
Daughter Juli is the heroine Cosmos - in long white boots, stockings and suspenders. Her mother is a cat called Mog, and her father a warrior turtle.
Cosplay involves dressing as manga heroes
Juli Martin said she was to blame for the new hobby - known as costume play or cosplay - after seeing it at a convention in Paris.
"I saw some people with cosplay and thought that was fabulous, like acting, very funny," she said.
"A lot of people like manga but not a lot of people understand cosplay, but think they will understand, it's just a question of time."
However, it is not likely that France's more traditional heroes will disappear just yet.
Kimyang Damasse at publishers Glenat believes it is not a threat, as manga caters for a different market.
"We have seen the emergence of new readers," he pointed out.
"The readers are not coming from the traditional comic books sector, so it's a totally different readership."