08/16/2012 01:47 pm ET Updated Aug 23, 2012

'Dexter' Season 7 Trailer: Could Dexter Kill Deb? (VIDEO)

After a steady stream of shorter, intriguing teasers, Showtime has finally released a dark, intense full-length "Dexter" Season 7 trailer that really ratchets up the anticipation for the new season.

The trailer spotlights several significant plot-points and previews the key conflicts of the season. Expanding on the footage Showtime released of the first two minutes of the season that featured the tense confrontation between Dexter and Deb after she walked in on him wrapping up Travis Marshall's dead body, the new trailer shows more of her struggle with whether to turn him in. The pressure brings their relationship to its breaking point.

As Deb catches on to the full extent of Dexter's serial killing history -- "It's the same amount of plastic wrap, the same positioning," she says of the Ice Truck Killer case -- the trailer takes a decidedly dark turn. "If you don't get off my ass, something bad is gonna happen," Dexter warns, as we see a shots of him injecting her steak with his tranquilizer. "The only thing worse than not knowing what she'll do, is not knowing what I'll do," Dexter says ominously.

There are other walls closing in on Dexter as well. Louis Greene, the creepy video game programmer who was interning with Miami Metro last season, has taken his fixation with Dexter to another level, saying in a web video that he wants to see him "lying in a pool of his own piss." Dexter responds by flashing his demonic side, strangling Greene against a wall, and later injecting him in the neck.

The trailer also reveals that Deb isn't the only person at Miami Metro who's on Dexter's trail. He accidentally left one of his signature blood-slides at the scene of the Marshall killing, and LaGuerta connects the clue's dots back to the Bay Harbor Butcher investigation. Miami Metro could be re-opening that case, leaving Dexter as vulnerable as ever.

Another bizarre highlight from the trailer includes a shot of Dexter appearing to slice Masuka's throat. Let's hope that's part of a dream sequence, because with all this craziness going down, "Dexter" is going to need Masuka's comic relief. Either way, it's going to be a wild season.

"Dexter" Season 7 premieres Sun., Sept. 30 at 9 p.m. ET on Showtime.