Kendrick Lamar performs onstage during the 58th Grammy Awards on Feb. 15. (Kevork Djansezian/Getty Images for NARAS)

Thursday night, without comment or explanation, Kendrick Lamar tweeted a link to the iTunes store where fans could purchase eight tracks he never told them were coming. Surprise!

And just like that, the rapper's photo was sitting front and center on Rolling Stone's website, as more than 80,000 people re-tweeted his link and music critics scrambled to catch up with the collection, called "untitled, unmastered."

The public relations strategy du jour is a sneak attack. Tell no one what's coming — or let word leak out just a little to give folks a tease — and then drop a new release in their laps. Voila! Instant buzz and a presumption that whatever just came out must be so awesome that it had to be kept under wraps. The tactic obviously saves on publicity costs. But more than that, it ensures that the new release cannot fail to live up to the hype. Because, after all, there is no hype.

The bombshell drop worked beautifully for Beyoncé's 2013 self-titled album, so she employed it again this year, releasing the stirring video and new song, "Formation," the day before she performed it at the Super Bowl halftime show. Drake, U2 and even David Bowie have also stunned fans with unannounced recordings in recent years.

But the shock-and-awe approach has gone beyond the music industry recently. This week will see the big screen release of "10 Cloverfield Lane," a new J.J. Abrams thriller that was kept completely secret until a trailer was posted online in January. Comedian Louis C.K. also used the strategy in January when he sent fans a six-line email announcing the availability of "Horace and Pete," an online show co-starring Steve Buscemi that he'd never previously discussed.

And the folks over at Funny or Die were somehow able to keep the world from knowing that they'd convinced Johnny Depp to play Donald Trump in their satirical biopic, "Funny Or Die Presents Donald Trump's The Art of The Deal: The Movie."

The 50-minute film's screenwriter, Joe Randazzo, who previously edited the Onion, explained the appeal of a surprise launch in an interview with the Comic's Comic. "So, rather than risk putting time and energy into promoting something that might get lost or underperform, just spring it on the audience so they learn about it and react to it for the first time, at the same time. People might also be more likely to have a positive reaction to something that just appeared out of nowhere. The holy s— gets mixed in with, and overwhelms, everything else. But it creates a conversation that everyone has at the same time, and that's priceless. It feels like an event — much like made-for-TV movies used to be in the 80s. We don't really get that anymore, except by surprise."

The strategy also takes advantage of the consumer urge to keep up. By dropping a new release that no one knows anything about, producers put audiences behind the proverbial eight ball. And the inclination follows: Better buy it now if you want to understand what your friends will be talking about at brunch. 

"It's about taking advantage of that impulse — impulse buying, impulse listening," says Jonathan Hay, a veteran producer and publicist in Los Angeles. "The next day is going to be a different trending story. So we want to be ahead of that new thing."

But, he adds, "that's what scares me now. How long is new? Six, seven hours?"