Frequency (film)

Frequency is a 2000 film directed by Gregory Hoblit and written by Toby Emmerich. John Sullivan (Jim Caveziel) is the adult son of a firefighter, Frank (Dennis Quaid), who died on the job when John was a child. John discovers that during the Aurora Borealis he can use his father's old ham radio to talk to him 30 years in the past. Using his knowledge of the past thirty years, John changes history, saving Frank from dying. They soon discover that changing the timeline has drastic consequences. A serial killer known as the Nightingale Killer had died in the old timeline - but in the new timeline, John's mother, a nurse, was not called away due to Frank's death, and thus she was able to prevent the killer's death in the hospital. In the erased timeline, the killer claimed only three victims - but in the new timeline he kills ten women, one of them John's mother.

Working across a span of thirty years, John and Frank work together to stop a serial killer, who soon sets his sights on the Sullivans...

Not to be confused with the obscure Rhythm Game of the same name.

Tropes used in Frequency (film) include:

Arc Words: "I'm still here, Chief." Appears in contexts ranging from Frank assuring little Johnny that he's still supporting him on his bicycle to Frank showing up in the present--having quit smoking to make sure he lived that long--to save adult John from Shepard.
Big Damn Heroes: John's father rescuing him in the present.
Butterfly of Doom: John saves his dad... but kills his mom. Unusually for the trope, he fixes that too, eventually, along with fixing everything that was wrong with his life.
Chekhov's Gun: Literally.
Crowning Moment of Heartwarming: "I'm still here, Chief."
Delayed Ripple Effect: Shows up in a few places, notably when John makes the first notable change in the timelines and when the killer is fighting both John and his father in both time periods.
Earn Your Happy Ending
For Want of a Nail
Going Cold Turkey: How Frank Sullivan apparently quits smoking.
Halfway Plot Switch: Goes from touching story about a son reconnecting with his dead father into a Set Right What Once Went Wrong thriller. And it works.
It's Personal:
- Once Nightingale starts to go after John's mom, it is so on.
- He may not 100 % know what's going on, but The Nightengale knows who to blame

Nightengale: Time for me to steal your life away.

It Got Worse: John gets quite the surprise the day after saving his father when he finds out that there are six more victims in the Nightingale killings than there were pre-changing history. The killer was never caught. And one of the victims was John's mother (who unknowingly saved the killer's life in the new timeline). Cue Halfway Plot Switch.
Meanwhile in the Future
Locking MacGyver in the Store Cupboard: The way Frank uses his firefighting knowledge to rig electrical wiring, a metal door, coffee, a spraycan and a lighter smacks of this.
Never Got to Say Goodbye
Nice Job Breaking It, Hero: See Butterfly of Doom, above.
Phone Call From the Dead: The plot involves the main character's ability to communicate through time with his long-dead father through a ham radio.
Playing Gertrude: Elizabeth Mitchell is two years younger than Jim Caviezel while playing his mother. More appropriate when she plays the mother in the past, though.
Portal to the Past: Though it can only transmit sound, it gets a lot of creative use.
Ripple-Effect-Proof Memory: After changing the past, John discovers that he remembers both the old timeline and the new one.
- Somehow averted with Shepard. His brain should have been going nuts with deja vu and new timelines while he's fighting with the Sullivans in their respective time periods.
San Dimas Time: Possibly the best portrayed example in movie history.
Serial Killer: The Nightingale Killer.
Set Right What Once Went Wrong: The film is an extremely satisfying complete embodiment of this idea.
Slow Motion Drop: Frank's helmet hits the pavement when the warehouse building explodes.
- Also, a highball glass slips from John's hand when the timeline resets during Frank's rescue from the warehouse fire.
Slow Motion Fall: Frank and the girl he is rescuing fall out of a burning building into the Hudson River.
Timey-Wimey Ball
Trust Password: Frank learns through John's future description of the ongoing 1969 World Series and the warehouse fire that John is indeed his son in 1999. Frank, in turn, uses the World Series knowledge in order to convince his cop friend that he's telling the truth about John and that he's being framed for the Nightingale murders.
Write Back to the Future: Used by Frank to get fingerprint evidence to his son 30 years later. Also, to a lesser extent, scratching "STILL HERE" into the kitchen table.