Castle Fan Video Reveals How Many Times Detective Esposito Says "Yo" (VIDEO) Tweet June 18, 2012 by Wetpaint Entertainment Staff Related: Castle, Javier Esposito Credit: YouTube Yo, Castle fans! Check out this awesome fan video of Detective Esposito uttering his favorite expression: Yo! How many times, you ask? According to this vid, a total of 90. That's a lot of yo's!