WHAT IT’S ABOUT NYPD Det. Raimy Sullivan (Peyton List) grew up believing her father, Frank Sullivan (Riley Smith), was a bad cop who had been killed in a shootout in 1996 — right around the moment the Yankees beat the Braves in the World Series. Then, one day, she finds her Dad’s old ham radio. Whom was he talking all those years ago on that radio? She’s about to find out: He was talking to her, in the future, or in 2016. When they both realize they’ve made a connection across time, she gives him enough information to save him in that shootout. She then begins to wonder whether he might know something about a notorious unsolved serial murder case — the so-called Nightingale one. Through the radio, they speak to each other across the years. Can she save her father? Also, what does her boss and his former partner, Lt. Satch Reyna (Mekhi Phifer), know about her father’s activities?

MY SAY Along with the movie of the same name, “Frequency” is drawn from a famous idea in — gulp — quantum mechanics. It states that a particle exists simultaneously in two dimensions, each with a separate reality, and each with a separate timeline. Sounds difficult until you realize this has also been the stuff of a thousand other movies and TV series, from “Twilight Zone” to “Fringe.” The “alternate universe” twist here is the ham radio: Information is relayed back and forth between the timelines’ protagonists, who alter their timelines until they both finally converge.

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In the Greg Hoblit and Toby Emmerich 2000 movie with Dennis Quaid as the father, and Jim Caviezel as the son, they spoke back and forth until they got the Nightingale killer, and reunited as father and son in present time. The film was a clever jigsaw puzzle that worked because relatively few pieces had to be assembled by viewers in less than two hours.

But that is also your giant puzzle of a potential problem for this CW newcomer: how to keep all the pieces in order, or how to keep them from multiplying until viewers’ eyes glaze over as they hopelessly lose track of them all. The pilot does keep the story intact — Raimy and Frank work across the planes of time to solve crimes and just maybe even get them to a point where they can think about being together again.

It also hints at the future of the series: That for every action undone, there is an inevitable reaction in the other timeline. That reaction can be good (saving Frank) or not so good. NBC’s “Timeless,” by the way, is not dissimilar except that “Frequency” is a time-travel series without the actual time travel part. The distinction may seem trivial but it’s not. Both Frank and Raimy are co-authors of their own personal histories. How they write it together, or mess it up together, could make an intriguing cop procedural.

Of course the alternate-universe version of “Frequency” is always a possibility, too: This could simply turn into a bewildering one.

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BOTTOM LINE Clean, well-told opener that keeps the movie within its sights. The future is the big question here.