Frequenting cinemas is prohibited because most of what is screened is harām (forbidden) alongside the playing of music which incites fitnah (temptation) ― and because it is a waste of time that busies a person with that which brings no religious benefit. In these times a Muslim is in severe need of occupying his time with that which will benefit him, his family and the Muslim ummah. And visiting cinemas is a barrier to the remembrance of Allah and to the fulfilment of religious obligations due to what occurs [in the cinema and in movies] of free-mixing between sexes and other types of corruption.
(See Al-Jāmi’ fī Fiqhil-‘Allāmah Ibn Bāz, p. 1205)
My comment: Movies are fictitious and made-up (untruths) to give people a sense of escapism and fantasy―quite often blurring the boundaries between fact and fiction leaving audiences unsure, confused and even mentally disturbed. Many films contain explicit sex scenes, immoral, lewd and adulterous relationships, extreme violence, killing, rape, sexual exploitation of women, drug abuse, drinking of alcohol and offensive language―all of which has a corrupting effect on the minds of viewers. Some of the most depraved and lowly immoral film characters (male and female) become role-models for movie-watchers and for large swathes of the population. Large numbers of people (and especially young people) copy the risky, immoral and dangerous things they see on the screen. Many of these films glorify unbelief, idolatry, magic and mockery of religion. None of this is good for our families or for society at large, and only encourages sinful behaviour―and things will only get worse until people wake up and rectify themselves and their families. We need to occupy our time with beneficial activities that help build our relationship with Allah and with our families and let us choose pastimes that nurture our bodies and souls and make us better people.