J.D. tells us that things got "mighty dull" (8.364) after the Great Brain's reformation. How dull? Papa doesn't even bother to find out where Tom is when suspicious things occur. Whoa. Just like that, the Great Brain's mischievous ways slink into retirement.
Or do they?
See, we're thinking the Great Brain's reformation is all a ploy to throw suspicion off of him. After all, there are tons of sequels to this book, and there's no way Tom just twiddles his thumbs in them. For now, though, J.D. at least believes the reformation is genuine.