She teams up with Ayushmann Khurrana the movie.
"She is very excited about the role... She is looking forward to it because she wants to play the role to complete perfection," said a source close to the actress.
"She wants to be well-prepared before she faces the camera for the film, which is why she will be devoting time to specially prepare for her part well in advance," added the source.
To understand lawyers, their body language and general demeanour, the makers are scheduling Sonam's meetings with young professionals.
Meanwhile, the actress has just wrapped up shooting "Ranjhanaa" and is looking forward to the release of Rakeysh Omprakash Mehra's "Bhaag Milkha Bhaag", in which she will be seen opposite Farhan Akhtar who plays the title role.
Mumbai Roundup: 9 incidents that took place this week
Photos: Ajay Devgn, Parineeti, Tabu at 'Golmaal Again' trailer launch
Photos: Dipika Pallikal Karthik oozes oomph in bikinis and sarees
Photos: Kareena Kapoor Khan's grand birthday bash
Photos: 'Dangal' girls Sanya Malhotra, Fatima Sana Shaikh's dinner outing