I saw this movie about 10 years ago. There is a serial killer who hides his victims bones around america. The detectives/reporters daughter has gone missing and she goes to him to find out if he killed her or not. he sends her around finding the bones to mess with her. in the end he kills himself and she finds out the serial killers mother is keeping a child captive and she believes it is her daughter so goes to get her, taking police with her
theres a part where the murderer kills a dancer, i think it might have been a ballerina
The Bone Collector (1999)
https://www.imdb.com/title/tt0145681/
I was going to answer the Bone Collector – I see someone beat me to it 🙂
https://en.wikipedia.org/wiki/The_Bone_Collector