? it's 'cause you make me smile ? Next to an ABC news investigation. Fake tickets for converts and sporting events. Our correspondent going after that potentially shady deals. Here's ABC now.... See More
? it's 'cause you make me smile ? Next to an ABC news investigation. Fake tickets for converts and sporting events. Our correspondent going after that potentially shady deals. Here's ABC now. Reporter: The hottest concerts of the summer like beyonce and Billy Joel are often the hardest and most expensive tickets to come by. But what if those tickets you buy are fake? And tonight, an "ABC news" investigation revealing just how hard it is to get your money back if you've been ripped off. That's what happened to Dakota Sal. She spent $600 on two tickets to a sold out Bruno Mars show in Los Angeles from a seller she met on craigslist. They put a big old void on my e-ticket and handed it back to me and said, "Sorry, these are fake tickets." Reporter: She never got to see the show and neither do so many others. Every year, nearly 5 million fans buy counterfeit concert tickets. And tonight, we learned even the experts can't spot a fake. To me, they look indistinguishable. Correct. They're -- you can not tell -- the both of these look exactly like real tickets. There is no way to tell. Reporter: We wanted some answers, so we arranged to buy Billy Joel tickets for $350 off of craigslist. You got the tickets? Yeah. And these are legit. Yes. All right, cool. 200, 20, 40, 60 -- Excuse me. We're with "ABC news" and we know that these tickets aren't real. Why are you selling people fake tickets? We have proof here that those tickets aren't real. I don't know what you're talking about, miss, to be honest with you. Miss, can we have our money back? Nothing like seeing Mara yell to try and get her money back. Did you get it back? Reporter: I did not, David. I didn't think so, but in the meantime, this was craigslist and don't they have a warning on their site? Reporter: They warn consumers about scams and they can't protect you if you get a bad ticket. You won't get your money back from them. But there are discount sites that you can go to where you will get a refund. Reporter: There are authorized dealers like stubhub where if you do get a bad ticket, you reach out to them and they will refund you.
This transcript has been automatically generated and may not be 100% accurate.