Castle and Beckett follow Gage's blood trail to a street corner with a camera. Beckett shines her flashlight at the camera, but in the next shoot, of said camera, it is first dark and then the light is shone on it.
Despite being first aired in 2012 this episode feature a library shot of the Brooklyn Bridge with the New York waterfalls project, which ran 4 years earlier (June 26, 2008. They ran from 7am to 10pm, until October 13, 2008).