Annie (Pauline Yeung) has the power to turn invisible in this comedy. She was chased by a malevolent spirit and ended up attempting to hide herself in a mud pit.
As she stood up, she was completely covered and her friends gave her a hosedown to wash the mud off her to prevent the spirit from seeing her.
This somewhat reminds of the scene from Invisible Woman (1983) whereby Alexa Hamilton's character was accidentally pushed into a pool of mud at a construction site