This study conducts an extensive doctrinal and constitutional examination of adultery law in India, documenting its progression from ancient religious and customary practices to colonial criminalisation and subsequent constitutional decriminalisation. Adultery was historically regarded as a moral and matrimonial transgression governed by personal laws; however, the introduction of Section 497 of the Indian Penal Code, 1860 (Now Replaced by the Bharatiya Nyaya Sanhita, 2023), redefined it as a gender-biased criminal offence based on Victorian morality and patriarchal concepts of marriage. The provision, which regarded women as passive entities and safeguarded male property rights, faced minimal opposition until its annulment by the Supreme Court in Joseph Shine v. Union of India (2018). This research will examine the legal journey of adultery from colonial law to Constitutional reinterpretation. It will trace the origin of adultery as a criminal offence under colonial law, analyze judicial approaches prior to decriminalization, and discuss the treatment of adultery under various personal and matrimonial laws. It concludes that while decriminalisation was a progressive step, comprehensive reform is necessary to align family law with constitutional values, ensuring dignity, autonomy, and non-adversarial dispute resolution in marital breakdowns.