Watching such films or TV series does not make a person disbeliever  but it is not permissible to watch  movies which entail evil or when it is feared that one may be led astray.
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We have forwarded this question to a number of prominent Shiite religious authorities and the answers which we have received are as follows:[1]
Grand Ayatollah Khamenei (may Allah grant him long life):
Only watching movies with blasphemous contents does not take one out of the fold of Islam. However, watching such films or movies which entail evil or when it is feared that one may be led astray is not permissible.
Grand Ayatollah Makarem Shirazi (may Allah grant him long life):
Watching such films does not imply disbelieving or being an unbeliever. However, there is no doubt that if watching them entails moral and ideological evil, one should avoid them.
Grand Ayatollah Noori Hamedani (may Allah grant him long life):
If what has been mentioned in the message leads to promulgation of infidelity and perverted or false beliefs, it is not permissible.
Grand Ayatollah Saafi Gulpaigani (may Allah grant him long life):
Generally speaking, it is not permissible to watch films or TV series which your beliefs and morality to become corrupt, although one who does not confirm or testify their contents is not considered to be an unbeliever (kafir).
Ayatollah Hadavi Tehrani (may Allah grant him long life):
Playing such games is not permissible, if they are going to weaken or influence your beliefs. However, only playing them does not take you out of the pale of Islam.

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