If you’ve been lucky enough to watch any of the four seasons of Sherlock, PBS’s 21^st century take on Arthur Conan Doyle’s famous sleuth, you may have noticed some story elements that take the saga well beyond razor-sharp deductive reasoning, a villain named Moriarty, a pistol-packing sidekick, a deerstalker cap, and a 7 percent solution.

Aside from complex sexual preferences, this Holmes, acted wonderfully by Benedict Cumberbatch, resorts to computer coding, hacking, smart phones tricks, lightning-fast Internet research, GPS tracking devices, social media, and DNA analysis.

The writers for Sherlock are not alone in the challenge they faced while writing a detective story in the era of Instagram, CSI, and Edward Snowden.

While you’d be hard pressed to find a technological advance as dated as a clamshell phone or a tan IBM desktop in an episode of Columbo or Murder, She Wrote, any murder-mystery writer who doesn’t want his protagonist to look like a clueless boob needs to create a gumshoe with some rudimentary awareness of technology. Without that savvy, the villains of today would have an unfair advantage. That holds true whether the bad guy is running a botnet scam from Moscow, is a 400-pound hacker living with his mother as he plunders bank accounts, or just a nerdy teenager who knows enough about coding to be dangerous.

As an editor at Bloomberg News, I got a leg up in educating myself on how the technology of our day can be exploited by criminal elements. I reviewed scores of stories about hacking and cyber-weapons and had to factcheck reporting against court filings and annual reports by computer security firms on who had been the intruder, what they got, how they did it, and what might be done to prevent more of the same.

In a just-released cyber-thriller, The Hacker Chronicles, I was able to put this knowledge to good use when I pitted a young hacker against the forces of evil in Russia, China, and Israel. Armed with viruses of his own and access to a system of city-wide surveillance cameras that record everything in sight like a desktop time machine, he turns detective to solve a murder.

But even if I had chosen to make my thriller about a plain detective and a simple murder, Sam Spade style, I would have had to have my character deal with modern-day challenges, such as what information can be found on a victim’s hard drive or how to get access to it if it had disappeared. Even if Lt. Columbo came back as a 21^st century detective the way Sherlock has, at a minimum he’d probably have to find some friendly geek to help him out on whether key evidence had been Photoshopped or why he doesn’t have to go down to the dusty hall of records any more to do his research. Readers, many of whom seem to live online, are just too knowledgeable about cyber-crime and other things cyber to let an author get away with anything less.

Don’t get me wrong. Critical thinking and paying attention are still at the core of any detective story about an unsolved murder. It’s just that the tools that aid that process have changed. Any author who hopes to connect to an audience that checks Facebook as they roll out of bed needs to keep up with technological advances to be credible. And if you want to be cutting edge, you need to factor in things like Apple’s “Find My iPhone” feature that can serve as a cheap tracker for a mobile device that was stolen—or planted—or StingRay, a police technology that permits cops to set up a phony cell tower to locate nearby callers even if they think they are protected by using an unregistered “burner” mobile they plan to dispose of in short order, drug-dealer style. I’ve used that latter one myself.

Of course, there is a way around all this bother if dealing with disposable SIM cards is not your thing and you just want to pen an old-fashioned Agatha Christie yarn or some noir tale about a shamus in a fedora: Set it back in a time before the modern world made things more complicated. But even this is going to take more effort than it used to.

You’ll have to do some research on technology of the day—or the lack of it—as I had to in another book I’m working on. In The Sleeper List, a spy thriller that starts right after the fall of the Berlin Wall, an unwilling sleeper agent is working in a nascent Silicon Valley. To avoid any anachronism as the hero eludes U.S. and Soviet investigators, I had to create a very detailed timeline of where technology was at that time. I calculated that he’d have an Intel 486-chip PC on his desk and be running Windows 3.0 as the Internet was just coming online and everyone was excited about this thing called email.

You can ignore this advice, of course, and hope for the best. But the result may be some cranky one-star reviews on Amazon or Goodreads faulting you for technical knowledge that seems to stop about the year Sherlock faced Moriarty at Reichenbach Falls.

Patrick Oster was managing editor at Bloomberg News for more than a decade. His previous thrillers are The Commuter and The German Club. The Hacker Chronicles was published April 14.