By day, Jason Hawes and Grant Wilson are ordinary plumbers. But as soon as they're off the clock, they become the paranormal investigators of Sci Fi Channel's Ghost Hunters. The reality series, which airs Wednesdays at 9 pm/ET, follows the Rhode Island natives as they attempt to track down things that go bump in the night.

TV Guide Online: How did you get interested in the paranormal?
Jason Hawes:
I founded The Atlantic Paranormal Society (TAPS) about 15 years ago after I had my own personal paranormal experience. Before it happened, I never believed in anything I couldn't see. After the experience, [the paranormal] became a passion.
Grant Wilson: I'd had experiences when I was in my teenage years that I just couldn't explain. You go looking for answers for those kinds of events and you don't find them out there. I met up with Jason and we became good friends. We have the same kind of mentality toward it all.

TVGO: So why plumbing?
Hawes:
Plumbing is a problem-solving field and a lot of that exists in the paranormal. Also, you've got to admit that it's a recession-free industry.

TVGO: But if the paranormal is your passion, why not devote all your time to that?
Hawes:
We get paid to be plumbers — we don't charge for our [paranormal] cases. It actually costs us money. Last year alone, I spent more than $20,000 just getting people back and forth to cases.

TVGO: You really don't charge for your services?
Wilson:
This field is full of speculation, and as soon as you start charging money for something, people start questioning your credibility.
Hawes: If we charged, we'd only be able to help certain people. It's also the ethics of it all. How can we charge for something that we can't 100 percent prove scientifically?

TVGO: How has TAPS evolved over the years?
Hawes:
When I started TAPS, it was supposed to be just a local group, but we grew to have 46 other bases in the United States and 14 other countries.
Wilson: We've got people in Florida, Colorado, California, Texas, New Zealand, Belgium — you name it. And we're constantly looking for more.

TVGO: What are your criteria for new members?
Grant:
We look for people who have their own life and just have a healthy interest in the paranormal. If you're an electrician and you've ever wondered if there's anything else out there, perfect. But if you're 45, live in your mom's basement and know how to play "Halo" really well, we don't need you.

TVGO: What do your families think about your extracurricular activities?
Hawes:
My wife has really been the backbone behind TAPS. Without her, it wouldn't exist. We just had twin boys six months ago, so it's been tough, but she still allows the door to be open.

TVGO: What was your most frightening paranormal experience?
Wilson:
I was in one where there was a 9-year-old girl and she was throwing stuff around and talking like a sailor. Her body was also contorting in weird ways. What was scary was that I had to contain her unnatural strength without hurting her 9-year-old body.

TVGO: How about your most frightening plumbing experience?
Hawes:
One time, Grant and I tried to move a 500-lb. hot water tank up two flights of stairs. I popped out my back and it put me out of commission for a while.

TVGO: Do you get many crank calls?
Hawes:
We went on a case in New Jersey where the guy actually built a speaker into his wall to try and get us to believe his house is haunted. We've also gotten calls where people tell us their toilets are levitating.

TVGO: Do people ever call you expecting the Ghostbusters?
Hawes:
I think they realize [the difference] when we don't walk in with Hoovers strapped to our backs.
Wilson: We like to stress the fact that we are paranormal investigators. We basically go locate, validate, educate... and I dunno, a bunch of other "ates."

TVGO: Be honest — is any of this staged?
Wilson:
All we can say is that the evidence we catch on the show really happened. What caused it, we don't know. It's that simple.