The actress has a new alter ego in the form of Letty Raines

Credit: Taylor Hill/FilmMagic

Michelle Dockery‘s first character after playing Downton Abbey‘s prim and proper – and, sure, a bit conniving – Lady Mary Crawley is anything but upper crust. In fact, she’s falling-down drunk, vomiting, doing drugs and engaging in sex scenes worthy of Kemal Pamuk himself.

In a racy trailer for TNT’s upcoming drama Good Behavior, Dockery’s Letty Raines acknowledges, “I’m a piece of s—. Why keep fighting it, you know?”

And though the trailer features a running track of self-help affirmations (“Today, I feel good. I have a lot to be proud of … I am the best me I can be. I am utterly, perfectly, me”), it’s clear that Dockery’s thieving con artist is running off the rails at every chance – sometimes even with a Southern accent.

Even before Downton wrapped up its run on U.S. screens this past March, Dockery has been keeping a low profile since her fiancé’s unexpected death from a rare cancer in December. She was first spotted in public that month while filming on the show’s North Carolina set.

Good Behavior is set to premiere this fall on TNT.