The worst question they can ever ask is to analyse a particular scene/extract/verse/page etc... which happened in 2005. Otherwise, most of the other questions can be found to be closely related to the syllabus description of this module as well as the examination rubric. The questions aren't really that unpredictable. So far, all past exam questions can be easily tackled by relating themes and techniques to the unique aspects of the text.
If you want to prepare an essay for this, make sure you analyse and relate the techniques and their themes down in great detail, because this allows you to be flexible with most questions. For any question you are confronted with, make sure you can answer it effectively by incorporating anything relevent to it from your prepared material with you own ideas developed on the spot. Never memorise an essay word for word just know it's ideas and key points.