Whiplash (1998)

Super hot insurance fraud investigator Angie Green goes undercover to investigate allegations of bizarre sexual practices at the Cracker Clinic, a facility that specializes in low cost physical therapy for female accident victims. Posing as a patient suffering from a neck injury, poor Angie finds herself on the wrong end of some sadistic medical atrocities perpetrated by a smiling female therapist with a taste for female flesh bound, gagged and suffering. Pretty Angie is stripped, and then bound spread-eagle on an exam table where she endures a host of indignities including being zapped with a stun , a "massage" with a cat o' nine tails and a 2 quart enema, complete with butt plug.