All perfect praise be to Allah the Lord of the Worlds. May His peace and blessings be upon Prophet Mohammad and upon all his family and companions.
Nightclubs that are set up for gambling, dancing, nudity, and other prohibited activities are considered among the major sins. Allah The Almighty Says (What means): "O you who have believed, indeed, intoxicants, gambling, [sacrificing on] stone alters [to other than Allah], and divining arrows are but defilement from the work of Satan, so avoid it that you may be successful. Satan only wants to cause between you animosity and hatred through intoxicants and gambling and to avert you from the remembrance of Allah and from prayer. So will you not desist?" [Al-Ma'idah/90-91]. Allah has also forbidden the spreading of corruption and immorality on earth. He Says (What means): "Indeed, those who like that immorality should be spread [or publicized] among those who have believed will have a painful punishment in this world and the Hereafter. And Allah knows, and you do not know." [An-Nur/19]. Additionally, Allah warns by Saying (What means): "And do not cause corruption upon the earth after its reformation. That is better for you if you should be believers." [Al-A'raf/85].
It is forbidden for a Muslim to go to so-called nightclubs or casinos, as it is also prohibited to work in such places. These venues involve major sins and immoralities, such as gambling, drinking alcohol, dancing, nudity, prohibited mixing of genders, and similar activities. They serve as means of spreading immorality and corruption on earth. And Allah The Almighty Knows Best.