I think we can drop the verb altogether. Using يعمل doesn't sound natural. I'm copying the rest of the sentence from your other thread (please, always give full sentences):
The horror in Cell works on a deeper, more frightening level than as a metaphor for the untenable choices we face when responding to a violent threat.
I suggest this translation:
الرعب في هذه الرواية أعمق وأقوى من مُجرد تشبيه مجازي
cherine, I think this sounds natural and does a good job reflecting the nature of the horror without focusing on finding a verbal equivalent for the English "work," which just doesn't seem to fit when looking for equivalent expressions in Arabic.