Is it permissible to listen to podcasts of series that contain unveiled women, while avoiding watching them?

Listening to serials via the radio is permissible, provided they do not contain شرعية ( Shar'i) prohibitions such as distracting musical instruments, and do not divert the Muslim from his religious and worldly duties. It has been reported from the Prophet (ﷺ): "The lawful is what Allah has made lawful in His Book, and the unlawful is what Allah has made unlawful in His Book; and what He has remained silent about, that is among what He has pardoned." Nevertheless, a Muslim's time is too precious to waste on such things. It is more fitting for him to spend it on what is more beneficial for him in his religion and his worldly life. It has been reported from the Prophet (ﷺ): "Two blessings which many people lose are health and free time."