"The Girl with the Curl" is episode seven of season two of Bones, the forensic drama series based on the books by Kathy Reichs.
Human Remains Are Found
Brennan and Booth are at a sewage treatment works. A body has been found, and it's in a very poor state. Brennan quickly identifies the bones as belonging to a young girl, no more than 9 or 10. The sewage works has over 1,800 miles of piping coming in from five different states, which doesn't narrow down the search area to any useful degree.
The Victim - With Extensive Cosmetic Work
The first reconstruction of the little girl doesn't bring up anything in the missing persons database. Then it's discovered that the girl had dyed hair, extensive dental work and make up, which totally transforms her appearance. By about two decades. Then the girl's image matches a junior beauty pageant (and those beauty pageants look to be really sick at best and borderline child abuse at worst) competitor who disappeared six months prior.
The Father is a Suspect
The mother blames her ex-husband, which she did at the time their daughter disappeared as well. However, it seems the father simply wanted to get his daughter away from her mother and what she was doing to their daughter. More evidence of cosmetic tampering - such as a corset, for crying out loud; they're really not pleasant even for adults - turns up, as well as medicines with serious side effects that were never prescribed. The child abuse seems to be rather less than borderline. The mother claims that everything was done at her daughter's wishes, but she does seem rather too focused on the winning of the beauty pageants. The mother also had an argument with her daughter half an hour before she went missing. Brennan and, indeed, everyone else, does not seem impressed by what was done to the daughter in the name of beauty.
Office Relationship Drama
Angela asks Brennan's advice after Hodgins asked her out on a date (they have been flirting a bit). On personal matters. Brennan thinks she's a weird choice for advice on such matters. Cam gives some rather more helpful advice, but then she and Booth slept together at the end of "The Truth in the Lye". Which Hodgins and Angela both twigged to.
Not a Pleasant Episode
Unless the dead girl turned out to be a total sociopath (which is possible; the dead girl was apparently not very nice to the others, but she didn't really qualify as being this), this was never going to be a nice episode, with such a young victim. It takes a turn for the even more unpleasant as well by the end.