Provider: Eastern (ET) Change
Alexis believes that a death-row inmate was wrongly convicted, so she seeks investigative assistance from her dad. However, they only have 72 hours to reexamine the original murder case before the inmate's scheduled execution.
Castle's thrown into an alternate universe during a murder investigation, and Beckett, Esposito and Ryan view him as a stranger in this world, so he must persuade them to let him assist them. Afterward, Castle finds the experience very inspiring.