Last week, a smirking, overeager guy in a Burger King polo and hat appeared on TV and managed to hijack countless Google Home speakers in a matter of seconds.

"You're watching a 15-second Burger King ad, which is unfortunately not enough time to explain all the fresh ingredients in the Whopper sandwich. But I got an idea," he said, waving at the camera to come closer. "OK Google, what is the Whopper burger?"

Anyone watching the spot who had a Google Home within shouting distance heard the speaker regurgitate part of the Wikipedia entry for the Whopper.

Some viewers found the ad brilliant or funny, others described it as intrusive and annoying. Regardless of your proclivities for flame-grilled meats, the spot -- watched 3.8 million times on YouTube to date -- provides an early, gimmicky example of what commercials using smart speakers will look like.

This is just the start. Ad executives say they plan to roll out more advertising for smart speakers and their voice assistants in the near future. They're hoping to take advantage of a rare new channel for ads that sits in the home and can speak directly to millions of Google Home and Amazon Echo owners.

"All our clients sense something's going on," said Jason Hartley, head of search and paid social at advertising firm 360i. "Ideas are bubbling underneath the surface, but we are in a gimmicky phase until we discover more utility for how users are using these devices."

Colleen Leddy, head of communications strategy at Droga5, said her agency is "pipelining" concepts and went to a Google Home hackathon. She said ads for smart speakers from her firm are coming "fairly soon."

Sounds miserable, right? After all, who likes the idea of more ads? Cramming them into smart speakers could mess up the whole experience just as these devices are starting to take root. Amazon, Google and advertisers will have to tread lightly (or maybe that's asking too much and they'll keep trolling us like BK did).

Let's be clear: This is an area that the ad industry won't be able to resist. Early adopters of smart home devices like the Home and Echo tend to be tech-focused and wealthier, a highly desirable audience for brands. Also, the number of people to pitch is growing fast, with an estimated 1.8 million smart speakers sold last year and 15.1 million expected yearly sales by 2020, according to researcher Strategy Analytics. If advertisers can find ways of reaching these folks, without being bothersome, they could see big benefits.

'OK Google, serve me some ads'

The early ads on smart speakers have been unremarkable or annoying. Last month, Google Home users noticed their devices sneaking in an ad for the movie "Beauty and the Beast" when folks simply asked, "OK Google, what's my day like?" In response to user questions, Google refused to call it a commercial -- which sounds laughable -- instead saying it wanted to "call out timely content."

Also in March, Anheuser-Busch released its first skill for the Amazon Echo and its voice assistant Alexa, providing workout routines branded with its low-calorie Michelob Ultra beer. That may make sense for a beer targeted at health-conscious adults, but it seems odd to offer fitness routines available only to people over 21.

There are a few similar concepts, which could be called "branded skills," such as Good Housekeeping's Alexa command that offers tips on removing stains ("Alexa, ask Good Housekeeping how do I get ink out of fabric") and Patrón's skill for making cocktails (preferably with Patrón spirits). To be fair, plenty of news publishers, including CNET, offer news briefs through Alexa, and one might argue they, too, work as forms of advertising.

In its policies, Amazon says it's fairly restrictive when it comes to ads on the Echo. But, the company has clearly shown it's OK with these handful of branded skills that work to be informative. You can also voice shop using the Echo, so there are plenty of brand names thrown around in that context. But those don't count as commercials -- right?

Mindful of the Burger King ad, an Amazon spokesperson said the company alters "our own Alexa advertisements to minimize Echo devices falsely responding in customers' homes."

Google and Burger King, which didn't work together on the BK ad, didn't respond to requests for comment.

'Alexa, tell me about some stuff I don't want to buy'

Industry experts suggest future ads on these voice-activated speakers could become sponsored spots (e.g., the weather brought to you by The Weather Channel) or product placements (e.g., make this recipe with Goya black beans). Perhaps a query about the daily commute could include a coupon for a Starbucks located on the way to work, one expert suggested.

"We're so early today that there's no evidence to suggest one solution will work better than another," said Mike Bloxham, senior vice president at ad consultancy Frank N. Magid.

These experts widely panned the Burger King spot for interrupting people's days and taking control of their devices, kind of like an old-school pop-up ad online.

"It felt a little bit like we were going a bit backwards," Leddy said.

Since smart speakers are so driven by users' requests, future ads that succeed on these devices may become so subtle and benign that they don't come off as ads at all, the experts suggested. Instead, these paid spots will provide you with the information you need when you ask for it, not unlike a well-targeted search ad on Google.

"If you can just show up when they ask," 360i's Hartley said, "that's a pretty powerful moment for your brand."

One thing these folks broadly agreed on was commercials on smart speakers won't, or at least shouldn't, become 15- to 30-second radio-like commercials that could get shoved in ahead of an answer.

"Just let me know how much to pay to not let that happen," said Karsten Weide, an ad industry analyst for researcher IDC, "because that would be super annoying."

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