Renfro wants to know the whys and hows of McKellen's past, and blackmails the old man into telling him Holocaust stories each day after school. McKellen doesn't have many whys in his repertoire, but overcoming his fear of being unmasked, begins to delight in finding an audience for tales from his past. Apt Pupil is interesting for the way it shakes up our sympathies. At times we're apt to want to like both the old man and the boy, until one or the other unsheathes his streak of sadism like a glimmering drawn dagger. McKellen is set in his ways, but the malleable Renfro's life is turned upside-down by his obsession with evil.
Curiosity leads to complicity, and finally to identity.
Apt Pupil isn't a brilliant story, and it strains credibility more than once, but like most anything Stephen King has written, it's a page-turner. A page-turner that, however incompletely or lightly, touches on some deeper questions of human identity.