'Celebrity Exorcism' Special Put Shar Jackson Through Supernatural Boot Camp

Shar Jackson's full up on chills, screams and terror for this Halloween after observing -- and surviving -- a real-life exorcism inside one of Hollywood's most infamous haunted homes.

The former "Moesha" star signed on for the experience, which was filmed for a special called, "Celebrity Exorcism." Shar was joined by "Full House" star Jodie Sweetin, ex-NBA star Metta World Peace ... and an actual exorcist.

The foursome went inside L.A.'s Rosenheim Mansion, where "American Horror Story" famously filmed. Shar told us on "TMZ Live," they actually had to get training before entering the home ... which has a dark history of murder, suicide and torture.

Yes, there's apparently a supernatural boot camp, which Shar says was intended to steady their nerves before the exorcism. It's pretty debatable whether the training did a damn thing, based on what Shar says here.

We know this ... never count on a 6'7" NBA champ to protect you from spirits or demons. Check out Shar's account of what went down in the mansion. Sorry, Metta ... some ghost stories just gotta be told!!!