Americans Hate Tingle: To put it simply, the show isn't nearly as popular in the U.S. as it is in Canada despite its support from CBS.
Awesome Music: The songs that play over the last few minutes of each episode tend to be pretty fitting/awesome. A list can be found here.
The show's own, unreleased music is also pretty good, but sometimes it transcends to superb. During the fourth episode, Asking For Flowers, a woman has taken the abusive husband of her sister hostage; we get three variations on the same theme. First a sharp, harsh take as the husband manages to get the gun and starts choking out the woman while the team listens in. Then a longer, slower version while Parker distracts the husband with a phone call and tries to convince him to deescalate, without admitting they know what's going on, building into optimistic as the tactical part of the team sets up their entry. Finally a drums version as he hangs up on Parker and makes as if he's going to shoot the woman, and then turning into relaxed horns to go with Ed Lane's "Put the gun down!" and the husband being cuffed and brought out.
Cargo Ship: Many people tease Spike about Babycakes and how she was his "girlfriend".
The episode "Good Cop" is about a cop who gets demonized by everyone because he accidentally shot an innocent kid. A year after that, the death of Trayvon Martin happened.
The series finale "Keeping the Peace, Part 2" is haunting considering that it aired in Canada the night before the Sandy Hook Elementary School shooting in the United States.
That episode may also be harder to watch after the Boston Marathon bombings that occurred a few months later.
Moral Event Horizon: Any time a hostage taker deliberately executes a hostage, most notably Misha Kondrashoff in "The Fortress" and Goran Tomasic (while his wife wasn't a hostage at the time, he shot her in the back, in cold blood).
Also the plane hijackers in "Grounded" where they planted a few of their own among the passengers and when someone tried to be a hero, they shot him down.
Whole-Plot Reference: The third-season episode "Collateral Damage" borrows a number of elements from The Fugitive, including the plot of a wrongfully-convicted man using a prison transport crash to escape and attempt to clear his name.
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