Syd's all, so, like, what? Good Ethan isn't really Good Ethan at all? Spy Daddy's all, yeah, that's a distinct possibility. Syd's all, well, then, who the hell is he? Spy Daddy's all, uh, we think it's the Scientist Dude, Marcovic. Syd's all, okay, there is NO way that Good Ethan is Marcovic; we shared boo-hoo stories about our dead fiancé(e)s! He tried to kiss me! He's hot! Vaughn's all, okay, we'll discuss the whole desperation kiss thing later, honey. Right now, I want you to check out this shot of someone who looks just like Good Ethan hanging out in a phone booth about three inches away from Detonated D'Overbite. Then, just for good measure, in case we're all in a coma, we're shown a CIA file with Good Ethan's visage on it. Yep. It's him. Good or Bad.
Oops Center's Conference Room Of Endless Expositions. Jack's standing next to a big-screen TV, spouting more clone/gene-splicing crapola. Basically, having a little handy-dandy clone machine around would be very good for international terrorism (read: Osama Bin Laden could tog himself out as Donny Osmond and no one would be the wiser) and very bad for national security (read: everyone hates Donny Osmond, but not enough to kill him, and therefore Osama would be free to run rampant over the land, wearing a coat of many colors and singing pop ditties from days gone by.)
Syd's all, how's this possible without huge scars and shit? Jack's all, it ain't surgical, sweetheart. A patient's genetic code is altered to reshape their physical attributes. Syd's all, is this reversible? Jack's all, honey, it ain't even POSSIBLE in the first place, but for the sake of the rest of the show, I'll just answer, "Dunno." There's more blah-blah-ing about how it only works on certain genetic dispositions, and the recipient has to be in a comatose state for several days while their cells regenerate, and you can only tell the real person from the double by an ocular scan.
Wendy Kroy: Okay, they haven't figured out how to clone anything better than a SHEEP in two hundred and fifty years, but this Marcovic idiot figured out how to clone a human in ONE EPISODE?
Regina: Shhhh. Just think about the Ethan.
Kendall's all, yeah, so, really, that just means that we still can't be sure if Good Ethan's really good or not. Syd's all, dude? Did I mention the kissing? And the shared sad sack stories? "He's on our side," she states emphatically. Over in The Clone Confirmation Center, Good Ethan's getting his eyes checked for cloning. He passes with flying colors.