It tells the story of an Indian multimillionaire family, which faces troubles and misunderstandings over their adopted son's marriage to a girl belonging to a lower socio-economic group than them.

Initially scheduled for the Diwali festivities of 2001, the film was eventually released in India, the United Kingdom and North America on 14 December 2001.

Yashvardhan "Yash" Raichand is a rich businessman, living in New Delhi with his wife Nandini, his two sons, Rahul and Rohan and his mother and mother-in-law, Lajwanti and Harbans.

As an adult, Rahul falls in love with Anjali Sharma, a girl belonging to a lower social standing than him, against the wishes of Yash, who wants him to marry Naina Kapoor.

He asks his parents to let him go to London to pursue MBA as part of family tradition; but he does so in order to conspire with Anjali's sister, Pooja to bring his brother and sister-in-law back home.

As a part of their plan Pooja informs Rahul that Rohan is her friend's cousin "Yash" who has shifted from India to London to pursue his studies and needs a place to stay.

Once there, Yash expresses his guilt for disowning his elder son, and adds that Rahul was foolish enough for believing that his father did not love him.

However, on the advice of his cousin, filmmaker Aditya Chopra, who thought that the male characters would be too weak, Karan decided to tweak the story-line to make it the story of two brothers.

[17] Before principal photography could begin, Karan and the contracted costume designers (Manish Malhotra, Shabina Khan and Rocky S) shopped in several locations of the US, London, Milan, and New Delhi to get the right look for each of the cast members.

[19] The first schedule of the film began in Mumbai on 16 October 2000, with the picturisation of the song "Bole Chudiyan" involving Roshan, Kapoor, Khan and Kajol.

Shooting locations include the Millennium Stadium, Bluewater in Kent,[27] Blenheim Palace, St Paul's Cathedral and the banks of River Thames.

[29] The crew faced enormous difficulties while filming an emotional scene between Jaya Bachchan and Khan at the Bluewater Complex, as a massive crowd had gathered there to watch them at work.

[30] Another song sequence ("Suraj Hua Maddham") involving Khan and Kajol was shot with the backdrop of the Pyramids of Giza in the city of Cairo in Egypt.

[36] She further stated that the buildup to the story was juxtaposed with the backdrop of two contrasting places – the Raichand home and the interiors of Chandni Chowk.

[37] Writer Sangita Gopal analysed the "intensification of the aesthetic effects of Hindi cinema" in the narrative scheme of the film.

During the confrontation scene between Yash and Rahul Raichand, a "thundering background score" coupled with "360° panning shots" were used to build up melodrama.

She added that while such scenes simply began by reprising previous face-offs in several melodramatic Hindi films (such as Mohabbatein (2000)), they gradually shifted "to a more realist register as the framework moves from a sociology to a psychology of the family".

He referred to the song "Suraj Hua Maddham" as an extradiegetic sequence that allowed Rahul and Anjali to be physically intimate "in ways that they could not in the real world of the film."

He added that the characters conveyed a plethora of emotions not through extensive dialogue but through the exchange of glances, which were demonstrated by extreme close-ups on their eyes.

[39] Writing for the book Movie Blockbusters, Andrew Willis commented that the film was specifically written to appeal to the Indian diaspora.

He explained that the film was aimed at invoking nostalgia among the large section of NRI's in Canada, United Kingdom and North America.

[42][43] According to Eckstein, several sequences convey a "culturally conservative" and "idealistic image" of India, while maintaining that the diaspora living in Britain lead a life of "involuntary exile".

[49] The use of "Jana Gana Mana" by Rabindranath Tagore during the film was met with criticism from a certain section of the audiences, and politicians of the Bharatiya Janata Party, for being "out-of-context" and "insulting the national pride".

[50] Subsequently, a writ was issued against Dharma Productions in the Allahabad High Court by a petitioner based in Uttar Pradesh.

It received praise for its visual richness and the performances of the cast, but criticism towards the lengthy run time, the script strength and inconsistencies.

Khalid Mohamed of The Times of India applauded the film in a five-star review: "K3G is the complete commercial banquet delivered with fabulous finesse by Karan Johar.

"[57] Contrary to the positive reviews, Anjum N., writing for Rediff, said that despite an extraordinary cast and a big budget, "Karan Johar disappoints."

"[53] Namrata Joshi of Outlook gave a mixed review and said that while the film "makes you laugh and cry alternately", the shenanigans were nevertheless "fake and affected" and "monochromatic despite the profusion of colours".

"[61] Derek Elley of Variety said that it "is a highly enjoyable, often dazzlingly staged vehicle dragged down by a sluggish final half-hour".

[73][74] In an interview with Filmfare, Karan Johar said that he was not dejected to have not won many awards at the ceremony, as he felt that Lagaan was "a classic" and deserved to win.