At a one-day hearing, Hugo's descendants argued that Francois Ceresa's "Cosette or the Time of Illusions," which is already in bookstores, violates intellectual property rights and betrays the spirit of the original novel.
"The characters have been kidnapped," said Pierre Hugo, the author's great-great- grandson, who is seeking a halt to publication and asking for $594,000 in damages from the book's publishing house, Plon.
He says he would donate the money to charity to promote culture.
"Authors should have a little imagination and do something different," said Hugo, 53.
Ceresa's book brings back the cast of Hugo's 1862 work - sort of.
Cosette, once a mistreated orphan, is a docile housewife in the sequel. Marius, the dreamy revolutionary who loves her, has become a spoiled bourgeois husband.
Worst of all, Hugo's family says, is the new Javert. The obsessive police inspector drowns himself in the Seine at the end of Hugo's novel, tortured by self-doubt. But he comes back to life in "Cosette" - and becomes a nice guy.
"Victor Hugo loved his ending," Pierre Hugo told The Associated Press. "He wouldn't want anyone to change it."
In court on Wednesday, lawyers for Pierre Hugo and several other family members accused the publishing house of using the 19th century author's name to give the novel instant cache.
The new novel, which costs $20, is wrapped in a red ribbon reading "The sequel to Les Miserables."
"Cosette is 18 and doesn't know much about life," the book jacket reads. "Her husband, the Baron Marius Pontmercy, is 23. They are young, rich and beautiful."
The publisher says the book is meant as a tribute to Hugo's classic and follows a long tradition of literary homage. Lawyers for Plon also claimed that Victor Hugo had never trusted his family enough to allow them to handle his literary legacy.
"Hugo denied his descendants the right to intervene. He once wrote, 'My grandchildren are simpletons,"' said lawyer Jean-Claude Zylberstein, drawing some laughs during a three-and-a-half-hour hearing.
The court was expected to render a verdict on Sept. 12. Despite the legal wrangling, Plon plans to release a second installment, "Marius or the Fugitive," this fall.
A similar legal battle played out in the United States in recent months. When Alice Randall retold the classic Civil War novel "Gone With the Wind" from the point of view of slaves, she raised protests from Margaret Mitchell's estate.
In April, an Atlanta judge had blocked publication of "The Wind Done Gone," ruling that it violated the copyright of Mitchell's 1936 classic. Last month, a federal appeals court lifted the injunction on First Amendment grounds, and the novel has been shipped to bookstores.
By Angela Doland
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