The singer signed with Dr. Luke when she was 18 and is looking to be freed from her contract with the producer.

Speaking to Billboard, Kesha's lawyer Mark Geragos said: "This lawsuit is a wholehearted effort by Kesha to regain control of her music career and her personal freedom after suffering for ten years as a victim of mental manipulation, emotional abuse and sexual assault at the hands of Dr. Luke.

"The facts presented in our lawsuit paint a picture of a man who is controlling and willing to commit horrible acts of abuse in an attempt to intimidate an impressionable, talented, young female artist into submission for his personal gain. Kesha is focused on moving her life and her career beyond this terrible time."

You can read the lawsuit in full, via Billboard, here.

The most notable allegation contained within the lawsuit relates to (again, alleged) sexual abuse on the part of the producer.

It reads: "After forcing Ms. Sebert (Kesha's real name) to drink with him, Dr. Luke instructed Ms. Sebert to take what he described as 'sober pills' in order to sober her up. Ms. Sebert took the pills and woke up the following afternoon, named in Dr. Luke's bed, sore and sick, with no memory of how she got there. Ms. Sebert later learned that the 'sober pills' Dr. Luke had given her were...more commonly known as the date rape drug, allowing him to bring Ms. Sebert back to his hotel room and alone and rape her while she was unconscious."

The lawsuit, which is a very harrowing read, details further allegations of physical abuse against the singer.

Dr. Luke has immediately filed a counter-lawsuit against the singer, saying that Kesha is "engaged in a campaign of publishing outgragoues and untrue statements about Dr. Luke... in an attempt to extort [him] into releaseing Kesha from her exclusive recording agreement with Dr. Luke."

There will no doubt be more news on this as the story develops over the coming weeks and months.