Recapped and Mr. Skin have also posted reviews. It is beginning to look like any full frontal from Scarlett will be hard to see.

Seven minutes into the film, a fully nude Scarlett strips an unconscious Lynsey Taylor Mackay of all her clothes and then puts them on herself. The scene takes place in a room that is entirely white and it is lit from behind so Scarlett is mostly in shadow. Scarlett’s nudity isn’t as clear as we’d like but still visible enough to make out breasts and ass. On the other hand, Lynsey’s nudity is pretty clear for those who care.

One hour in, Scarlett strips off all her clothes in an entirely black room. We see a well-lit medium-far shot of Scarlett fully naked from the side as she slowly backs away to the right.

At 77 minutes, Scarlett is fully naked in a dark room that is only lit by the reddish-orange light emanating from an electric heater. The camera is behind Scarlett such that we can see her right breast and butt clearly, and then full frontal nudity in the mirror. Then there are several more angles of Scarlett nudity including straight on. Scarlett’s bush is mostly in shadow, but we can see her breasts and butt pretty well.

Lastly, at 85 minutes Scarlett shows her butt briefly from the side during a sex scene. Scarlett then shows her ass from behind as she examines herself.

http://www.recapped.com/tiff-2013-under-the-skin

(0:08) Scarlett Johansson is seen from a distance, showing breasts while leaning over the body of a motorcyclist. Buns as well when she stands up.

(0:58) Scarlett Johansson is in her bra and jeans. The bra comes off from the backside, and we see left breast from the side.

(1:15) Scarlett Johansson shows bare breasts while looking at herself in the mirror. She begins checking out different sections of her body. It's darkened with a reddish haze leaving it just a tad too dark to see everything full frontal, but there is at least one shot where you see the silhouette between her legs.

(1:22) Scarlett Johansson is stripped to black panties on the bed, then the panties come down her legs as a guy begins to screw her. After getting startled she moves to the end of the bed and uses a lamp to look between her legs, all of which we see from behind as her buns hang off the edge of the bed.

http://www.mrskin.com/breaking-nudes-toronto-scarlett-johanssons-nude-debut-confirmed---15255

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UPDATE: Tonight, I just received a very detailed review from a trustworthy source, detailing all of Scarlett Johansson's nude scenes in Under The Skin. This is the same source who gave me information about Sarah Gadon's nude scene in Enemy (which like Under the Skin, is also showing at the Toronto International Film Festival).

Basically, Scarlett shows full nudity front and rear, but some of it is from a distance, and most of it is dimly lit.

Here, in verbatim, is the review he sent me.

Scarlett has four nude scenes in the movie and countless others where she's in her underwear or showing off major cleavage.

First scene is just a few minutes in. Johansson is completely nude and stripping an unconcious woman of her clothing. Butt, boobs, and brief full frontal. Pretty lengthy scene. You see her head to toe all in one shot, but it's back lit at distance. It's not as clear as it could be, but it's all still there.

Second scene: All black void as her character seduces a severely deformed man. Starts off in her underwear and takes it off as she's backing away from the guy. Full frontal from the side at a distance. Best lit of all the scenes.

Third scene (and by far the best): Her character is examining her body in front of a mirror for a good few minutes. Numerous angles, front and back. Boobs, butt, and bush. Dimly lit.

Fourth scene: You see her butt when she gets up out of bed after having sex with a guy. Dimly lit but a good view.

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There are a number of reports, stating that Scarlett Johansson has nude scenes, including some full-frontal) in Under The Skin, which has screened at Telluride and just today has screened at the Venice International Film Festival. The question is how much can actually be seen.

Here is a Hollywood Reporter review mentioning the full-frontal nudity:

"Johansson herself is not the source of the film's problems. She totally commits to the part, to the extent that she even performs several scenes of full-frontal nudity. Unfortunately, many, if not most, of the people who ultimately will check out this film will probably do so solely in order to check out those scenes."

http://www.hollywoodreporter.com/race/telluride-under-skin-starring-scarlett-618843

However, the blogger behind the Batty for Nudity blog contacted another reviewer of the film, and he mentioned that the view is not clear.

On the other hand, some brief mentions of the scenes from people elsewhere makes it sound like quite a bit is actually visible. This film is coming to the Toronto International Film Festival next week so hopefully we will definitely know by then what can actually be seen.