LOS ANGELES — We've long come to accept that movies and TV shows needing to display a phone number onscreen will use the trusty, definitely nonworking "555" prefix — so much so that we're not even looking for digits to try anymore. Let's face it: Many moons have passed since 867-5309, and caller ID has pretty much ruined the art of the crank call, anyway.

So it's understandable that when Focus Features rolled out its ambitious and highly unusual trailer-release campaign for Self/less, we all missed a key element: a phone number that actually works.

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Focus went to some length to put its first Self/less trailer on the map, five months ahead of its July 31 release. Universal Pictures' specialty studio sent packages out to a select group of film reporters and bloggers, containing a new LG smartphone that was connected to the Sprint network, then pinged them all with text messages on Wednesday morning that led to the trailer, above.

But what we all seemed to have missed was this little number:

Image: Focus Features

"You'e reached Phoenix Biogenics," says the voice on the other line, referencing the fictitious company that, in the film, can perform a procedure that transfers the consciousness of an aging wealthy man (played by Ben Kingsley) into the body of a healthy young one (Ryan Reynolds). The voice prompts you to opt in for text messages that, presumably, will feature more content from the film as we get closer to the release.

Funny how old-fashioned that seems now, doesn't it?