Britney Spears Posts Creepy Skull Baby Photo Amid 'Red' Campaign

Britney Spears is going dark -- and "RED" -- with her recent Instagram posts ... but a disturbing black-and-white photo of a woman cradling a skull baby tops them all.

The singer's string of IG posts the past week has been baffling fans as she's been sharing photos of red objects -- lips, a refrigerator, gloves, and a kitten in a red drawer -- along with videos of herself dancing ... and captioning them "RED."

But, on Monday night she dropped this creepy Victorian era photo with a skull-faced baby and wrote ... "Devil is in the details."

She added ... "wouldn’t want this baby to hit me one more time!!!!" with some LOL emojis, an obvious reference to her 1998 hit, and one she found amusing.

Shortly afterward, Brit shared a dance vid of herself with the caption, "I'm an extremely wicked looking vampire but really that's the whole point !!!!"

In the vid, she's wearing the same outfit as similar RED-themed vids she's shared over the last 6 days.

The bizarre posts come as Britney fans are ramping up the #FreeBritney movement, and she's requesting changes in the ongoing legal battle over her conservatorship. She is NOT, however, requesting to end the conservatorship.

Some of her fans believe the posts are cryptic messages to the public about her life, while others believe they are simply indicators she's not well.