Nicolas Cage had something he clearly wanted to get off his chest when he hit up a karaoke bar … because his rendition of “Purple Rain” was … emotional.

Nic was at a joint Sunday in L.A.’s Koreatown when he tried his hand and vocal cords on the classic Prince song, and we’re guessing the performance was fueled by his desire to annul his recent marriage of 4 days.

You can watch the video at TMZ HERE.

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