A community group in the Indian city of Calcutta says it has been sued by JK Rowling, the author of the Harry Potter books, for breach of copyright.
The Hindu version of Hogwarts, under construction
The group has been building a huge model based on Hogwarts School of Witchcraft and Wizardry as part of celebrations for a Hindu festival.
A court in the capital, Delhi, will start hearing the case on Friday.
Next week's Durga Puja festival is a huge event in eastern India - thousands pay homage to the Hindu goddess Durga.
The BBC's Chris Morris in Delhi says that popular themes are recreated using massive models made of canvas, wood and papier mache.
Our correspondent says that the festival has never been a problem before.
JK Rowling is one of the world's most successful authors
The community group is being targeted by lawyers representing Penguin India on behalf of JK Rowling and Warner Brothers who hold the rights to Harry Potter in India.
Members say that they make a different model every year - in the past they have built the Titanic.
This year they chose Hogwarts School - as well as life-size models of Harry Potter and his friends.
Organisers said a mock steam engine train is also being constructed next to it, to resemble Hogwarts Express.
Correspondents say the construction is nearing completion and is expected to cost around 1.2 million Indian rupees ($30,000).
But it is argued that the organisers did not seek permission, and so are being sued for breach of copyright.
If the court orders any payment to be made, the group says it cannot afford it.
"The summons has come at a time when the pandal (decorative structure) is almost ready. We don't know what to do now as we cannot afford to pay the fine," chief organiser Harinmoy Roychowdhury said.
Media reports in India suggest that possible fines could amount to two million rupees ($50,000).
The Durga Puja festival is avidly celebrated in Calcutta
Lawyers for JK Rowling say the money could well be donated straight to charity, but our correspondent says that plenty of people in Calcutta argue that JK Rowling and her lawyers are simply spoiling their fun.
"Sadly, the organisers of this large-scale commercially sponsored event did not approach us for permission to go ahead," Warner Brothers said in a statement in London.
"This event falls outside the guidelines set up by Warner Bros., JK Rowling and her publishers to help charitable and not-for-profit organizations to run small-scale themed events that protect fans and allow everyone to enjoy Harry Potter books, films and events in the spirit in which they were created," the statement said.
The four-day Durga Puja festival begins on 17 October and is the biggest Hindu festival in east India.
In Calcutta alone, more than 10,000 structures have been set up.