Last night's all-new 'Dexter' episode, "What's Eating Dexter Morgan," may not have ended up as game-changing as its previews might have led us to believe, but the Showtime serial killer drama still has some surprises in store for next Sunday's installment, "Scar Tissue." The first clip has emerged from Showtime, and it looks like Dexter still can't get past the thought of losing his sister from his life.

Following Deb's near-confession to a clueless Quinn, Dr. Evelyn Vogel (Charlotte Rampling) has shifted her attention off of Dexter and begun Deb's treatment for post-traumatic stress disorder, but the veteran Miami Metro detective may have come too close to her brother's dark secret, as well as her own disturbing deeds to ever involve Dexter in her life again.

Meanwhile, Dexter has another name for the ongoing "Brain Surgeon" investigation, but Dexter has seemed off his game lately and may end up chasing the wrong lead once again. If nothing else, Miami Metro has been thrown off the scent, so Dexter will be able to concentrate his efforts on finding the true killer. Of course, something tells us not to fully trust Vogel, even after the Brain Surgeon has been dealt with.

We'll hopefully see a preview of the remaining episodes of 'Dexter''s final season from the blowout Comic-Con 2013 panel, but in the meantime, check out previews for "Scar Tissue" above and below, and give us your 'Dexter' season 8 predictions in the comments!