Quite near the start - just after Alice is kidnapped, she is stripped naked. Her ankles are tied to the bed and her wrists handcuffed to the bed and she is also gagged. You see bare breasts and body, but no genitals. Photographs are taken of her by the kidnappers and then they put clothing on her. Strong theme of bondage throughout.
Two men are shown getting undressed and both of their butts are briefly seen. Their testicles are seen between their legs but they are shadowed.
You see them pull her trousers down revealing her naked torso in profile and hold a plastic urinal to her for her to go to the loo; the contents are dumped in the toilet. At one point she needs a "number 2", he gives her a bucket - she pulls down her trousers to use. No nudity here.