The campaign, by Mullen in Boston, part of the Interpublic Group of Companies, has a budget estimated at $7 million. The ads reiterate themes that have appeared in previous Zappos campaigns, which include “Powered by service” and “Happy to help. 24/7.”

There will be television commercials, print advertisements and video and display ads on Web sites, along with a presence in social media like Facebook and YouTube and on Zappos.com. The ads will also appear in an unusual place where Zappos is already advertising: on the bottoms of plastic bins in airport security lines, reflecting the origins of Zappos as a seller of shoes.

The campaign is centered on the interaction during phone calls between Zappos employees and customers. The employees are represented by puppetlike characters who are based on and styled after actual Zappos workers.

The characters, called Zappets, resemble Muppets who have been to the theater several times to see “Avenue Q.” The idea is to evoke the offbeat company culture for which Zappos has become known.

The genesis of the campaign was in observations by Mullen executives who, while competing last year in a review for the Zappos account, visited the company’s headquarters in Henderson, Nev., to spend time with the customer service representatives.

“We sat with them, and we had headphones on, and we listened to the calls and heard how much of the company’s culture seeped through,” said one of those visitors, Alex Leikikh, managing partner and director for account services at Mullen.

Another visitor, Mark Wenneker, managing partner and executive creative director at Mullen, said of the employees: “They would stay on the line for as long as you wanted to talk. They would talk about anything.”

According to Aaron Magness, director for brand marketing and business development at Zappos, the approach reflects that “our customer loyalty team is not scripted and is not measured on time of calls.”

“The goal is when you see the ads, in TV, print or digital, you’ll say, ‘That’s the Zappos I know,’ ” Mr. Magness said, “or, ‘That’s a company I want to do business with.’ ”

Some of the commercials use recordings of calls made to Zappos employees, whose voices are heard in the spots. The words “Actual call with Zappos” appear onscreen. The customer service representatives were not aware that the calls were potential fodder for an ad campaign.