Meethe Mein Kya Hai unfolds over four days during Diwali at the home of a family matriarch in Lucknow. Jai (Ritwik Bhowmik), a young widower, begins to find comfort and healing from his grief amid the warmth and festivities of a family reunion. However, the celebrations take an unexpected turn when his sister springs a surprise marriage announcement on the family. As multiple generations gather under one roof, old disagreements resurface, long-buried secrets come to light, and unexpected revelations turn the festive gathering into a whirlwind of humour, family friction and emotional confrontations. Through laughter, chaos and heartfelt moments, the film explores family bonds, relationships and the complexities of moving on.