Arush Mehra (Akshay Kumar) lives a fairly wealthy lifestyle in Sydney, New South Wales, Australia with roommates Tanmay Joglekar (Ritesh Deshmukh) and Ali Haider (Fardeen Khan). Arush works for a popular dance club, while Tanmay entertains children as 'Eddy Teddy', and Ali takes care of their apartment. Mostly he watches cricket and does betting on it. All three are womanizers and usually end up sleeping with different women. One day, they find a baby girl (Juanna Sanghvi) outside their door with a note instructing them to take care of her, since one of them is her father. The three men go to all the women they dated and slept with, but none claims the baby is theirs.
The men try to take care of the baby, but she becomes a huge pain. So, they drop her off at a house near a church. They the set of for a Christmas party. They are all thinking of the girl. A big rainstorm occurs, and the baby develops an illness after being caught in the rain. The three men stay with the baby in the hospital, realizing how much they love her. She recovers, and the guys become changed men. They love her, pamper her, and grow an attachment towards her. They name her Angel. One morning, a woman named Isha (Vidya Balan) comes to take Angel back, claiming the baby to be her daughter. The guys are shocked as Arush tells them about his past.
One year ago, Arush travelled to Delhi to attend his cousin Arjun's wedding. There, he met Isha Sahni, who also resides in Australia. He won her over and they spent the night together. Shortly after, Isha caught him in a compromising situation with Devika Sharma (Sindhura Gadde), Isha's friend, so the couple split up. It was not Arush's fault as Devika forced herself on top of him. Arush returned to Sydney and forgot about the incident.
The guys find it very difficult to live without Angel. Arush ends up challenging Isha to marry someone faithful within seven days who will accept Angel as a daughter. If she's unsuccessful, she will have to give Angel back to him. They sign a contract to finalise the deal. The men worry that they might lose the bet since Isha is beautiful and wealthy. Arush plans with Tanmay, Ali and Bharat, who is Isha's father in order to keep Angel with him.
His first attempt involves Ali posing as a botany professor named Parimal Tripathi who speaks very pure Hindi. Bharat is impressed by Parimal by this. They manage to get through a few days of the week until one day Isha asks him about marriage for the next day. After Isha says this, Ali talks to Arush and Tanmay who tell him to go to Disneyland where Ali gets Bharat attacked. He is stopped from further efforts by Tanmay in the 'Eddy Teddy' costume. Bharat decides that Tanmay is the right man for Isha. Tanmay, Arush and Ali make plans to stop Isha from marrying someone else. As the contract is about to terminate, Isha somehow manages to find out the truth that she has been cheated by her father, Tanmay, Ali and most of all Arush.
Isha goes with Angel to her private jet to go somewhere very far because she has lost the deal. As she is about to leave she is stopped by some cops because Ali and Tanmay called them. As they are arguing, Arush turns up showing Isha the contract and tearing it up indicating that Isha now has every right over Angel. But before the three men leave heartbroken, Arush says that a child needs a mother the most but it also needs a father. Just as they are leaving, Angel says her first word "Dada", but nevertheless Isha takes her away in the aeroplane.
The three men are depressed as they assume that they may never see Angel again until they are surprised to see her on their doorstep. Isha finally admits her love for Arush and the film ends with their marriage taking place, and Angel's photoshoot.Akshay Kumar as Arush Mehra
Juanna Sanghvi as Angel A. Mehra
Vidya Balan as Isha Sahni/Isha Arush Mehra
Fardeen Khan as Ali Haider/Parimal Tripathi
Ritesh Deshmukh as Tanmay aka Eddy Teddy
Boman Irani as Bharat Sahni
Aarti Chhabria as Ali's ex-girlfriend
Shahrukh Khan as Raj Malhotra (special appearance)
Anupam Kher as Mr. Malhotra
Payal Rohatgi (special appearance)
Sindhura Gadde as Devika Sharma
Chirag Vohra as Arjun
Muskaan Mihani as Arjun's bride
Anupam Sharma as the doctor
Jennifer Mayani the Supermarket Girl
Vrajesh Hirjee as Ajay Shah, bridegroom of Devika Sharma
Bikramjeet Kanwarpal as advocate Mishra, Isha's lawyer
Kim Sharma as Bharat Sahni's Girlfriend (special appearance)
Special appearance in title song (in order of appearance)Malaika Arora
Most of the shooting took place in Australia while some in Filmistan Studio in Mumbai.
An Australian features in a promotional video which was not to be in the film. The girl band from Sydney are called the Girlband.
The music is composed by Shankar-Ehsaan-Loy and lyrics are penned by Sameer.
The album received favourable reviews from major critics. Joginder Tuteja of Bollywood Hungama in his four-star review, said that the album is a "must buy": "The music score of Heyy Babyy is undoubtedly the best soundtrack of the year so far. Every track is a gem in its own way." Sukanya Verma of Rediff described the album as "a peppy soundtrack".
The album made its debut at No. 6 in the charts, later climbed up to the top 5 and remained consistent in the middle of the charts. According to the Indian trade website Box Office India, with around 12,00,000 units sold, this film's soundtrack album was the year's tenth highest-selling.
Heyy Babyy opened to positive reviews, though many criticised the slow pace in the second half. Taran Adarsh gave the film 4 out of 5 stars saying it "is an entertainer that has something for everyone". He praised the performances of the lead stars. Critic Aparajita Ghosh gave 3 out 5 stars, saying "Heyy Babyy packs in enough masala and emotion to keep you entertained throughout its running time." Noyon Jyoti Parasara of AOL India stated "Sajid Khan's debut is one movie you can go and watch and leave your brains behind. Go laugh aloud!"
Heyy Babyy opened to packed houses in over 650 cinemas in India. The opening was at 90%+ and continued to do well in the days following. It grossed ₹500 million (US$7.8 million) in India, $1.4 million in the USA and £763,000 in the UK and was declared a "super-hit".
It was a hit abroad, opening to a favorable response and taking the second biggest Hindi film opening in the UK after Salaam-e-Ishq: A Tribute to Love (2007). Heyy Babyy debuted at number 10 and made £289,761 at a screen average of £4,765.
The film released on DVD and was the first Hindi movie to also be released on Blu-ray disc.