The film stars Vijay Sethupathi and Ritika Singh, with Pooja Devariya, Nassar and Yogi Babu amongst others in supporting roles.

Gandhi Arumugam, an accountant, leaves his village near Madurai for Chennai with his best friend, Muthupandi "Pandi" Selvam, to get all the documents necessary for going to London, where they plan to make money to pay off their debts.

The middlemen claim that the British Deputy High Commission would prefer to give tourist visas to those who are already married, so the duo are forced to add their "wife's" name while applying for the passport, with Gandhi adding his "wife's" name as Karmeghakuzhali, following a suggestion from their real estate broker, Murugesan.

Eventually, the theatrical troupe are invited to perform in London, leaving Gandhi in a fix as he now needs to have his "wife's" name removed from his passport.

He successfully manages to track down a woman named Karmeghakuzhali, who is a television journalist, and tries to convince her to act as his wife and "divorce" him.

Later, Gandhi learns that Pandi was deported upon arrival in London by immigration officials for giving false information and address verification while obtaining his passport, and he too finds himself in the dock for doing the same.

[4][5] Ritika Singh was signed on to portray the leading female role of a journalist, only a month after the release of her first film Irudhi Suttru (2016).

The critic added that "Manikandan and his writing team (Arul Chezhiyan, Anucharan) should hold classes for other Tamil filmmakers who want the story-screenplay-dialogue credit but reveal little understanding of these elements" as "everything in Aandavan Kattalai is there for a reason".

[17] M. Suganth of The Times of India wrote, "Just like how Manikandan's Kaaka Muttai and Kutramme Thandanai refrained from finger-pointing and sermonising, Aandavan Kattalai, too, is far from being preachy, despite involving a subject that offer plenty of targets to take pot-shots at" and gave the film a high rating of three-and-a-half out of five stars.

[21] S Saraswathi of Rediff.com gave it 4 out of 5 stating that "the director once again delivers big time with a refreshing screenplay loaded with reality and fun, some great music, delightful characters and brilliant all-round performances".