Trivia: In a shot of Zeus sitting on the throne, Emma Thompson, in costume as Nanny McPhee, is actually hiding behind the throne - they were filming next to each other. The story was related during an interview - she sneaked on set during a break, sat on Liam Neeson's lap and said "I think you've been a very naughty boy". He suggested she stay when filming resumed, as the shot wasn't going to be on him anyway, but she didn't want to throw off Ralph Fiennes, so hid behind the throne to get out of the way, and a shot of it with her hidden behind, unseen, is in the movie.
Trivia: Like Tanedra Howard won a role in Saw 6, Gabby West won the second season of Scream Queens and is featured in this film. She is Kara, Evan's girlfriend. She is underneath one of the rear wheels of the car in the garage trap.
Trivia: The two 'disc jockeys' in the soundbooth of the 'End of Line' club are actually Daft Punk, the French group that created the movie's soundtrack.
Trivia: Glee's Dianna Agron makes a cameo appearance as Jack's fiancee, Natalie.
Trivia: Whilst this movie is a remake of the 80's Karate Kid, and is named the same, no actual karate is performed at all. It's all kung-fu.
Trivia: In the opening scene with Richard Dreyfuss fishing on the lake he is singing to himself "show me the way to go home". This is a nod to the movie Jaws because it is the song that he sang along with the rest of the crew as they waited for the tagged shark to be re-sighted. (00:01:00)
Trivia: When the foursome ski down the mountain and are looking around at the oddly dressed people, someone behind John Cusack says, "Hey Lane, you owe me two dollars". This was a nudge to John Cusack, who played Lane Meyers in "Better Off Dead" and was pursued in the snow by a crazed paper boy shouting "Two dollars!"
Trivia: John Travolta is handed a bag of burgers. He takes one out and hands it to his partner, and calls it a Royale With Cheese. A nod to Pulp Fiction, where Travolta explains to Samuel L. Jackson that in France, they call a Quarter Pounder with cheese a "Royale with Cheese".
Trivia: Sylvester Stallone sustained 14 injuries during filming, including breaking a tooth, rupturing his ankle and getting a hairline fracture in his neck that required the surgical insertion of a metal plate. He even had bronchitis and shingles during the shoot.
Trivia: Frank Moses' file, seen when Cooper is told he is his next target, gives Frank's date of birth as March 19, 1955. This is Bruce Willis' date of birth. (00:15:00)
Trivia: Make sure to stay after the ending credits to see Will Ferrell and Mark Wahlberg in a restaurant being quite comical.
Trivia: When Nancy is drowning in the blood, the blood breaks through the floor to pour into the bedroom downstairs. This is a tribute to the original's famous bed-death scene where Johnny Depp is slaughtered by Freddy, causing the room to be drenched in his blood. (01:23:30)
Trivia: Alice's impending battle on the "frabjous day" with a creature referred to as a "Jabberwocky" is a central plot point, and refers to Lewis Carroll's famous poem "Jabberwocky," from which other characters in the film, such as the Jubjub bird and Bandersnatch, are derived. However, the titular creature of the poem "Jabberwocky" was NOT a Jabberwocky, but a Jabberwock. For whatever reason, the writers of the film chose to call it by the [admittedly similar] title of the poem instead of the actual name of the creature. (For the full text of the poem, see http://www.jabberwocky.com/carroll/jabber/jabberwocky.html).
Trivia: McGregor finds that the BMW navigation system is active, and decides to follow the directions, having no idea where it will lead. There are obviously much easier and direct ways to check the entered target destination of a sat nav than actually following it. Instead of this being a mistake, it is most likely a script choice; portraying McGregor as stressed, technically unknowing, inexperienced driver of modern luxury cars, or all of that.
Trivia: When Jackie confesses that he was orphaned and lived in a group home, this is true for both his character and in real life. Jackie's parents gave him up to the Peking Opera House because they could not afford to raise a child. There he learned how to sing and acrobatics along with his "brothers and sisters."
Trivia: When Teddy enters the lighthouse, as soon as he begins to climb the spiral stairs, the camera follows his movement from in front of him. However, as Teddy and the camera wind around the stairs, the wall behind also appears to move with them, as though what is REALLY moving is only the staircase itself, rotating on its central axis. Yet another point (added to the various disappearing glasses/bottles) that adds to the general 'insane' feel of the film.