BONES: Exclusive Scoop on the Season Finale

Last week's episode of Bones proved that Hodgins was in fact haunting himself.

This week, it's Brennan's turn to be haunted by a ghost from the past, but as this David Boreanaz-directed episode reveals, in a far more insidious manner.

The dark tone and frenetic pace may leave you wondering if you've accidentally missed part one of a two part finale (don't worry, you haven't), but hang in there, because fans, particularly long-term fans, will be richly rewarded for sitting through this final revealing and disturbing episode of the season.

"The Nightmare Within the Nightmare" finds the team re-investigating "The Puppeteer," whom you may recall as the serial killer from earlier in the season who likes to dress, pose and feed his dead victims for months before finally disposing of their bodies.

While the team looks into the Puppeteer's latest handiwork, Brennan's sense of guilt begins to overwhelm her -- with disastrous consequences.

We've seen the finale a little early, thanks to our friends at FOX, and have a number of teasers to share with you.

No, we're not going to reveal any major plot points that would ruin your enjoyment of the final episode of the season. However, we urge you to proceed with caution anyway. One man's teaser is another man's spoiler, as they say. (Ok, it's only us who actually says that. But we tend to say it a lot, because we're serious about spoilers.)