This is more of a technical review rather than an plot synopsis. If you want that, check out
http://www.imdb.com/title/tt1659338/On a total impulse after seeing the promo on the "barker" chanel, I ordered this movie on demand Friday night. I remember hearing numbers stations fairly frequently in the 1980s when I was doing a lot of SWL, and figured it might be a good popcorn movie.
The movie looks OK, but as usual there's a lot of hardware overkill when it comes to Hollywood's interpretation of security. Think underground bunkers, "mantrap" gates, and bank vault doors all over the transmitter facility. Of course, there's no rent-a-cop at any of the gates or remotely viewed cameras over secure fiber links to the station, only a laptop computer that is running the typical Hollywood easy-hack operating system and several iMacs in the main transmitting room. There's no shots of transmitters or other radio equipment (I don't even recall seeing a mixer in the "studio") and there's no engineer or technical people at the site. Being an underground bunker, it's also very very dark all the time.
The plot requires a super-intelligent, but completely helpless woman, to read the numbers out over the air once a computer generates the cypher code. Of course given the mechanical sound of all the numbers stations I've heard, this is completely wrong, the voice might be female but is just a computer playing out audio files. This super-intelligent woman still manages to talk into the wrong side of the mic (a Neumann U87, which is mounted vertically with the capsule on the side
http://en.wikipedia.org/wiki/File:Neumann_U87.jpg). This is forgivable except that there's a big metal band that runs over the top, and you'd think the sound guy might point out the error to someone anyway.
At any rate, the way they describe the decode process isn't too far off from what most people accept as how it's really done, but greatly simplified. There's also a lot of plot holes that would become apparent when you realize that only one station had been compromised (that earlier was said to only send instruction to European operatives), yet instructions were sent to operatives all over the world. And again, I just couldn't get over the fact that an ultra secure location has almost no security or outside monitoring, nor was there any upper-level monitoring of the messages being sent. I don't want to give away too much, but suffice to say the whole system seems to be way too easy to game with far too little security to make sense.
The CIA guy assigned to the station does a lot of shooting, gets shot a lot and John Cusack does a good job of trying to make it an action-thriller. But the script really wants to be more of a mystery, or romance, or something. It certainly didn't have anything to do with radio.