Back in May, just after the network TV season ended, fans learned the shocking news that Sophia Bush will no longer be returning in "Chicago P.D." season 5. Neither the actress nor the show offered any details behind the sudden departure, sparking speculations that it may have been involuntary.

Now that the fifth season is underway and fans have seemingly moved on from her exit, Bush is finally clearing the air about the issue. It turns out it was her own decision to leave the NBC drama.

Responding to an Instagram follower who suggested that she may have been pushed out of "Chicago P.D." after four years, Bush insisted she left of her own volition.

"Took me a long time and a lot of hard work to get out of that show," she wrote. "I left because I wanted to. End of story."

She did not offer any more explanation, only asking the fans of the series not to "demean" her capabilities and "degrade" her position.

Bush had played Detective Erin Lindsay in "P.D." for four seasons. Her character was a member of the CPD Intelligence Unit and was partnered with Detective Jay Halstead (Jess Lee Soffer), with whom she had a romantic relationship. Lindsay's storyline was wrapped up by explaining she would be moving to New York to take a job with the FBI.

While there is no direct replacement for the character, "Chicago P.D." did bring back Jon Seda, who starred in the now-canceled "Chicago Justice."

After leaving the show, Bush signed with the upcoming film "Acts of Violence," where she will play another detective, Brooke Baker, who is investigating a human trafficking ring. According to One Chicago Center, she will star alongside Bruce Willis. The film has no exact release date yet, but it is expected to debut later this year.

Apart from the movie, Bush also signed a deal with 20^th Century Fox Television to star in a drama project and create new ones as an executive producer.