How does a budding boy band know when it has reached full-on heartthrob status?

Apparently, it's kind of obvious.

"It's gotten to the point where it starts to become scary," 98 Degrees' Jeff Timmons told the MTV Radio Network of the rabid fans that the group now attracts.

"They show up at our houses and call our parents and find our family and hunt 'em down, and even my grandparents are getting calls."

Of course, when you opt for the life of a pop phenom, you have to be prepared for such invasions. As the group's single, "The Hardest Thing," has climbed the chart, the boy band has kept an eye out for the occupational hazards that come with such success.

"If you're gonna try and be a singer and be in the limelight and have your music exposed, you're pretty much open to the other stuff as well. It's part of the job," Jeff concedes.

It's also a job that the guys in 98 Degrees seem to be excelling at these days. The group drew more than 4,500 fans to a recent in-store appearance in Los Angeles. Others who hope to catch a glimpse of the guys will be pleased to learn that they have signed on for the first-ever Nickelodeon All That tour after their current Heat It Up tour wraps up. The group will also turn up on the tube on "The Rosie O'Donnell Show" on May 13, and as part of a Disney/ABC special that tapes in May and airs in June.