Mike calls the next witness, Donna Paulson. But it turns out he's just practicing in the empty library with Rachel as Donna. Just as Donna promised to do, Rachel pleads the Fifth. (I'd think they could just get Harold to come in and decline to answer, if there were anything else for Rachel to do on this show any more) As Mike keeps pushing, Rachel keeps not answering. That is, at least until Mike seems to put "Donna" in the ground even without her answering any questions. Rachel says to Mike, "This is gonna be bad, isn't it?" Mike should probably not answer that.
In the hallways, Louis is unconvinced that the Mike vs. Rachel bit will swing the jury, which, according to Louis, responds to fear. So he slaps Mike with a subpoena on the logic that Mike knows everything about Harvey. Mike tries to dodge to the restroom, but Louis drags him into his office, where a polygraph is waiting, complete with technician. Soon Louis is asking Mike baseline questions, like his name and his occupation and... where he attended law school. Of course, Mike didn't. It looks like he's caught, but Louis pushes him. Mike finally says, "I'm proud to say I have a diploma from Harvard Law," which he does, even though it's as fake as Louis's smile. The technician nods, and Mike's had enough, saying this won't get them anywhere because he doesn't know anything about the case anyway. He gets out of the chair and says, "You want fear? I'll get you Donna." There's going to be fear all right if Mike gets up in Donna's grill, but I don't think it's what Mike is expecting.
So then it's Mike's turn to intercept Donna outside her building. She walks up to him, smiling, and then snaps, "The answer's no." Mike follows her down the sidewalk, reminding her she broke her promise she made him not to shred the document. She says she also promised her attorney not to talk about this with anyone at the firm, because she'd rather not go to jail: "I don't do roommates and I definitely don't do orange." Mike leaves her with this thought -- Harvey's taking the fall for her mistake and she's going to regret it for the rest of her life.