* ActorAllusion: Frank's mention of being a Marine with service in Vietnam. During ''Series/MagnumPI's'' run, Tom Selleck often wore a cap with the legend "VMO-2", which was a Marine Forward Air Control squadron out of Da Nang.
** Averted. The show is set and filmed on-location in UsefulNotes/NewYorkCity.
** The pilot had some interior scenes that were shot in Toronto, although exteriors used New York City proper.
* CastTheExpert: The show's technical advisor, Detective First Grade Jim Nuciforo (ret.) plays Frank's security guard.
* CreatorBacklash: [[spoiler: Amy Carlson did not approve on Linda being the victim of a BusCrash. It was her decision to leave the show, but she assumed she'd be invited back to give Linda a proper exit.]]
** Abigail Hawk plays ''Abigail'' Baker.
** Jim Nuciforo plays ''Jim'' the security guard.
* DirectedByCastMember: Donnie Wahlberg (Det. Danny Reagan) directed "Manhattan Queens".
* FridayNightDeathSlot: The current king of aversions; 7 seasons in the can and renewed for an eigth, all on Fridays.
* McLeaned: [[spoiler: Amy Carlson did not come back for Season 8, so Linda Reagan was KilledOffscreen.]]
* TheOtherDarrin: Nicky was played by a different actress in the original pilot.
%% * PlayingAgainstType: Michael Imperioli as an attorney instead of [[Series/TheSopranos a mob Capo]].
* PlayingGertrude: Tom Selleck is only 5 years younger than Len Cariou, who plays his father.
** Jack and Sean Reagan, Danny's two boys are played by real-life brothers Tony and Andrew Terraciano.
** In "Drawing Dead," Aida Turturro plays the shopkeeper questioned in an officer-involved shooting. She is a real-life cousin of Nicholas Turturro, who plays Sergeant Renzulli.
** Jennifer Esposito has coeliac disease and due to the condition, could no longer keep up with the grueling filming schedule required for her character. While the show writers were willing to work around it, [[http://www.hollywoodreporter.com/live-feed/jennifer-esposito-leaves-blue-bloods-381475 CBS were not]] and told the show to write her out, a decision she was ''not happy'' with.
** "Quid Pro Quo" was shot shortly after Hurricane Sandy hit New York City. The episode has Danny pay a visit at one point to a detective friend of his in the Rockaways, the part of the city hardest hit by Sandy. The shots of course being done on location in the Rockaways.
* TheWikiRule: [[http://bluebloodstv.wikia.com/wiki/Blue_Bloods_Wiki Blue Bloods Wiki.]]
* YouMightRememberMeFrom: Creator/TomSelleck's role as Police Commissioner Frank Reagan is his first major role in quite a while, apart from a string of TV movies based on the ''Literature/JesseStone'' book series. He mentioned in an interview on ''Series/TheTalk'' that he took the job partly because the script made him cry.