'Manhattan' Season 2 Spoilers: Twitter Reacts William Petersen, Rachel Brosnahan Premiere!

WGN America aired the highly anticipated Season 2 premiere of Manhattan. In Episode 1, Twitter had lots to say about Rachel Brosnahan (Abby Isaacs) and Olivia Williams (Liza Winter) returns with their new adversary, William Petersen (Col. Emmett Darrow).

As we previously mentioned, the second season will focus on the events leading up to Trinity test. This is the first detonation of an atomic weapon, which happened 70 years ago. While Charlie Isaacs (Ashley Zukerman) and Abby (Brosnahan) embrace and struggle with their unexpected new power on the Hill, physicist Frank Winter (John Benjamin Hickey), doesn't know how his A-bomb should be used. Meanwhile, Frank's botanist wife (Williams) battles with the top-secret compound's new commanding officer (Petersen).

In our recent recap, Charlie is working nonstop to deliver the first atomic bomb but the thunderous weather isn't helping. While Charlie struggles to take on the leadership role left behind by Frank Winter (John Benjamin Hickey), he tries to amend his relationship with Abby. With a traitor in his midst, Emmett knows more than he is telling as he orders Frank's arrest on sight.

In an interview with Entertainment Weekly, Zukerman teases what's to come between Abby and Charlie, "He's driven to do the right thing. He wants to be a better person, but once he's in the position of power, and finds out he has a baby on the way, he recognizes the sins of the past and tries to make this thing work. They do throw themselves back into each other's arms. That's as simple as it gets. She holds a special place in Charlie's heart."

Check out what Twitter had to say:

@Jeanette607 tweets, "Fall TV season just got a whole lot better: #ManhattanWGNA is back, with a bang(yes)! Great cast, with new additions,bolstering great story."

@Ana1007 writes, "#ManhattanWGNA is so good. Great writing and superb shots."

@amandapham states, "It's scary and sad how these women's issues are still relevant today. #ManhattanWGNA"

@popcornnmypurse mentions, "That's a helluva entrance, William Peterson. #ManhattanWGNA"

@magneticdynamo adds, "@ManhattanWGNA Drives me crazy Helen does so much & they can't even give the girl a real closet. #ManhattanWGNA"

@RachieBros exclaims, "So thrilled to hear the excitement surrounding the @ManhattanWGNA Season 2 premiere. Can't wait to show you guys the rest! #ManhattanWGNA"

Manhattan continues Tuesdays 9pm on WGN America.

Readers, are you excited for Season 2 of Manhattan?