If the average household light bulb measures about 60 watts, the electrical power of Carly Rae Jepsen’s ear-to-ear smile right now is about a 120. Were she indoors, you’d probably have to squint, but she’s outside at a table at a restaurant in Midtown Manhattan on an overcast afternoon in June.

The location is foreign territory for her, a 29-year-old Canadian now living in Los Angeles, but Jepsen’s informal pleasantness makes it feel like I just walked into her house. She is wearing a wide-brimmed black hat, a cream-colored, long-sleeved lace top, and that enormous smile that might be accentuated by her small frame. Her demeanor as we speak about her third album, E•MO•TION (School Boy Records/Interscope), coming Aug. 21, is so pleasant that it seems like she’s new to the industry, not someone who’s been fighting to be a part of it and writing songs since she was 17.

Jepsen is the singer-songwriter who has made some of the most infectious pop music of the last couple of years, beginning with “Call Me Maybe,” the ubiquitous single that launched her career in the United States back in 2012 and led to a thousand parodies on YouTube. It may have caught on without the help of a pair of tweets from Justin Bieber and Selena Gomez, who heard it on Canadian radio earlier that year, but those certainly did not hurt. Nor did the viral video that Bieber and Gomez put together shortly after of them lip-synching the song with a couple of their teen-star friends, like Ashley Tisdale and Moisés Arias. In fact, the cosign led directly to Jepsen getting signed to Bieber’s manager and SB Projects founder, Scooter Braun, and his School Boy Records label. “I had signed everything before I’d even met [Braun],” says Jepsen. “I just sort of trusted him on the phone. And I also felt that everything was happening because of him and Justin.”

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If “Call Me Maybe” began as a guilty pleasure for some, it quickly turned to an out-in-the-open pleasure for many. Billboard named “Call Me Maybe” its 2012 song of the summer that September, citing at the time that it had sold 5.5 million downloads, according to Nielsen SoundScan. Jepsen released her sophomore album, Kiss, that same month, and though it debuted at No. 6 on the Billboard 200, it never moved any higher, falling off the charts entirely after 11 weeks. Compared to the overwhelming success of “Call Me Maybe,” the album, though critically praised as one of the best pop releases of the year, was a commercial flop.

Three years later, Jepsen reemerged this March with “I Really Like You.” The song was another sugary ear worm similar to “Call Me Maybe,” though it was not as commercially effective, peaking at No. 39 on the Billboard Hot 100, despite a brilliant video starring Tom Hanks and free promotion from another Bieber lip-sync video.

And then something strange happened.

Jepsen was the musical guest on Saturday Night Live on April 4, and she performed “I Really Like You” for her first song. When the lights came up on the stage for her second song, Jepsen was flanked by Dev Hynes and Ariel Rechtshaid, two songwriters and producers who have worked with everyone from Sky Ferreira and Solange Knowles to Vampire Weekend and HAIM, “indie” artists who carry a certain cachet. Together with a backing band, Jepsen, Hynes, and Rechtshaid performed “All That,” a moody, slow number, drenched in ‘80s R&B sounds, that featured Jepsen pleading, “Show me if you want me, if I’m all that.” The track went up for sale on iTunes the next day, and though it didn’t have the numbers of “Call Me Maybe,” it started attracting a new crowd. People who turned up their noses at “Call Me Maybe” were playing this song. Pitchfork named it Best New Track. Collectively, the music world scratched its head because suddenly, Carly Rae Jepsen was cool.