Indian television's "Ugly Betty" Mona Singh, who is set to make her big screen debut with Aamir Khan-starrer "Three Idiots", says she is excited but also nervous about working with the superstar.

"Aamir is so good. It's not even funny. He makes me so nervous. In fact, the thought of working with any of the big stars like Amitabh Bachchan, Aamir and Shah Rukh Khan makes me very nervous. But for now, I am excited, " Mona told over telephone from Mumbai.

In "Three Idiots", which is based on Chetan Bhagat's best-selling novel "Five Point Someone" and is being directed by Rajkumar Hirani, Mona plays Kareena Kapoor's sister.

"I play a very bubbly character in the film and my look is very different from what I look right now. My role is really good and I have a major part in the climax of the film, " said Mona.

She became extremely popular when she essayed the role of ugly duckling Jassi in Sony TV's "Jassi Jaissi Koi Nahin". Her true identity was kept under wraps in the initial months of the show. Mona managed to win the viewers' heart as Jassi.

Now she is back to being in disguise on a new reality TV show "Arre Deewano Mujhe Pehchano". She would be competing with celebrity contestants Rakhi Sawant, Shweta Keswani, Mahesh Manjrekar, Yash Tonk, Gulshan Grover, Divya Dutta and Mandira Bedi to win the title of "Master of Disguise".

Commenting upon the format of the show, she said: "The show is all about stand-up comedy actually. It's about how well we can conceal our identity and find a scapegoat on the streets. It's quite a challenge for all of us and a very refreshing show."

Winner of two dance reality shows - "Jhalak Dikhla Jaa" and "Ek Khiladi EK Haseena", Mona is quite confident of her success on the show.

She said: "I think I will be good. I had successfully remained in disguise for 'Jassi...' so I might perform better than others. But my voice is a big giveaway. When I speak in Hindi, it has a very strong Punjabi accent so I have to work hard on it."

Right now Mona is seen in NDTV Imagine's hit soap "Radhaa Ki Betiyaan Kuch Kar Dikhayengi".

"I found the character interesting, so I took it up. Also, 'Radhaa...' is a very simple and sweet show and I used to watch it regularly, " she said.

For now, Mona is concentrating on "Arre Deewano Mujhe Pehchano" and "Three Idiots" and says some "interesting offers" are coming her way.