The programme follows Skyler's husband Walter White, who starts dealing drugs after finding out that he has cancer.
Gunn told LAist that Skyler will start to behave differently, saying: "In this season we really see Skyler acting out and breaking bad in her own way. You can even see it in the decisions we made about how she looks - what she's wearing, how she does her hair, and those kinds of things.
"She starts to form her own identity, because to me Skyler had felt like kind of an invisible person, the stay-at-home mum who takes care of all the details and hard work that no-one ever recognises or acknowledges."
She added: "This season you really get to see her implode and then explode."
Breaking Bad continues Sundays at 10pm on AMC.