Trisha was playing an anglo Indian girl in the film to be directed by Vetrimaran.
Apart from "Aadukalam", she also plans to quit a Telugu film in which she was paired with Balakrishna. The actress was said to have informed both -- Balakrishna and Dhanush -- about her decision. She has also promised the producers that she will return the advance money.
Trisha is doing so to accommodate dates for Hindi film offers, which might prove to be her passport to stardom in Bollywood.
According to the sources, Tamannaah or Ileana may replace Trisha in "Aadukalam". Since it's the role of an Anglo-Indian girl, it's more likely that Tamannaah with her fair complexion would get the final nod.