Talk about an exciting season finale on Bones!

According to E! Online, producers are planning to bring Zack back for the final episode of season four, though a deal is not finalized yet with actor Eric Millegan yet. 

Moreover, it's been confirmed that the wildly buzzed-about sex scene between Brennan and Booth will, indeed, take place. From there, season five will be all about the consequences of this hook-up, which begs the question:

Might Brennan be pregnant?!?

Chime in with your thoughts on that possiiblity now!

Matt Richenthal is the Editor in Chief of TV Fanatic. Follow him on Twitter and on Google+.