And then Warrick speeds up, leaps out of his car, and demands to know what he can do to help. Gil and Catherine decide to let him work off his energy by running with the bloodhounds that are trying to pick up Nicky's trail. Said trail goes cold right around a large rectangle of dry pavement amid the shiny, damp expanse. Warrick concludes, "There was some sort of large vehicle here," and we flash back to a large vehicle sitting directly under a torrential rain shower. Which...was not mentioned by anyone in any of these interminable bull sessions earlier in the episode. Warrick measures the dry space so that he might try and extrapolate the vehicle from the dimensions. He's got his little notebook in hand, and as he digs in his pocket for a pen, the music swells dramatically and he finds the coin he tossed with Nicky instead. Cue a guilt-triggered imagining of someone lifting Nicky's limp form, and a close, close, CLOSE-up of Warrick looking all torn up inside.
David the collected coroner lets us in on this fun fact: if should you ever be faced with a pile of entrails and the eternal question "Human or canine?", you can check for an appendix and a cecum. Humans will have an appendix. All mammals have a cecum, or a small pouch widely considered to be the start of the large intestine, which absorbs water and salts from undigested food. Dedicated carnivores like dogs will have smaller cecums than herbivores do, so I'm thinking that maybe David and Catherine are using the size of cecum to determine the species from which these intestines came. Anyway, David confirms that it's dog guts, Catherine sighs, "That's not going to help," and David says sincerely, "I'm sorry." As she stalks out -- since Catherine's Very Important Feelings preclude the necessity of acknowledging that other people's emotions have a right to exist -- David calls her name. She turns around and he asks, "Have Nicky's parents been informed yet?" "I told you, Gil and I are work -- oh. You mean his genetic parents. That would be my job." And off she stalks, leaving David to sigh over the dog guts.
Cut to Sara telling Gil that the Styrofoam cup yields no clues. Gil groans, "We're not going to get lucky with this guy -- he knows how to work clean." Liam comes charging on by to tell Gil that he's just pulled all of Nicky's active and recent cases. Gil orders, "I want to know who had a grudge against him: civilian complaints, death threats...there was a guy a couple of years ago that stalked him, he may be back." Liam assures him he's on it.