- Acting for Two:
- Cristián de la Fuente in "Friend or Faux."
- Acting for Five: Emily Rose as Audrey Parker, Lucy Ripley, Sarah Vernon, and as of Season 4, Lexie DeWitt and Mara. And, finally, Paige.
- Actor Allusion: Nolan North guest stars as an archaeologist who helps a character played by Emily Rose solve a supernatural mystery. Hmmm...
Lexie: Are you a cop?
- William (who is played by Colin Ferguson) in Season 4 is introduced thusly:
William: Not even a little.
- This isn't Christian Camargo's first time playing a serial killer, who is killed by his more positive brother.
- Casting Gag: Christian playing an old friend of Edge - aside from their history as tag team partners in the WWE, the two have been best friends since childhood.
- Directed by Cast Member: Jason Priestley (Chris Brody) directed "Lockdown" and "Real Estate", Lucas Bryant (Nathan Wuornos) directed "Enter Sandman", and Colin Ferguson (William) directed "Just Passing Through".
- Enforced Method Acting:
- The actors are never told spoilers, so that their reactions to any new development or revelation is genuine. The actors have expressed in interviews that they're dying to learn the truth about The Troubles and Audrey's origins as much as the fans.
- Emily Rose has stated that she used her frustration at finding out that she isn't really Audrey Parker and all of the training to be a believable F.B.I agent and the emotional life she had been building as an actor was basically not true as motivation and emotional subtext for how her character must feel about her own life.
- Fan Nickname: "Fraudrey" for the second Audrey Parker who showed up at the end of season 1. Ironically, it turned out that Fraudrey was in fact the real Audrey Parker and the first one is the fake!
- It's a Small World After All: The actors for Dwight and Nathan found out they grew up 20 minutes away from each other. Emily Rose (Audrey) noted they even share a very similar sense of humor.
- I Want You to Meet an Old Friend of Mine: Minor character McHugh is one of Dwight's helpers and is portrayed by William Reso. Reso's also best friends with Adam Copeland (who plays Dwight) and they had a successful wrestling career together before Haven.
- Name's the Same: Audrey Parker was the name of a One-Shot Character on The 4400.
- Out of Holiday Episode: Invoked in the Christmas episode "Silent Night," which was released around Christmas in reality but took place in July in-universe. Someone's trouble was creating Christmas in Haven by trapping the town in a snowglobe, and only Audrey, who is immune to the Troubles, knew something was wrong. Everyone else just assumes she's a Grinch for not liking Christmas (and thinks she's crazy when she says Christmas is not in July).
- Playing Against Type:
- Claudia Black's character (Moira) is rather frumpy, talks in an American accent, and is a total Jerkass.
- Colin Ferguson, known for playing genial, bumbling Everyman Jack Carter, turns out to be both evil and the Big Bad of Season 4.
- Croatoan, The Big Bad of the series, a quiet, gentle, soft-spoken sociopath is played by Large Ham Extraordinaire, William Shatner.
- Real-Life Relative:
- Lucas Bryant's wife Kirsty Hinchcliffe plays Rebecca Rafferty, a minor cop in Haven PD starting in season 4.
- John Dunsworth's (Dave) daughter Molly plays Vickie.
- Real Life Writes the Plot: Jennifer disappears in the Season 5 premiere because Emma Lahana had to go home due to a family emergency (she's from New Zealand and the show is filmed in Nova Scotia).
- Those Two Actors:
- Too Soon: "Reunion" was pulled at the last minute due to the Sandy Hook Elementary School shooting in Newtown, Connecticut. The episode, coincidentally, features violence in a high school. It was aired in mid-January instead.
Trivia / Haven