Complex sentence: Original stars of the TV series, David Hasselhoff and Pamela Anderson, made cameos in the film portraying The Mentor and Casey Jean Parker, the mother of C.J. Parker.
Split into simpler sentences: Original stars of the TV series, David Hasselhoff and Pamela Anderson, will make cameos in the film. They will portray The Mentor and Casey Jean Parker, the mother of C.J. Parker.