Love is in the air for millions of Americans tonight, but it's not just Cupid working overtime.
"Valentine's Day is a good day for lovers and it's an extra special day for private investigators," said Jimmie Mesis, private investigator and editor in chief of PI magazine.
He says it's the biggest day of the year for catching cheating significant others.
"It's very common for a cheating spouse to have lunch with one lover and dinner with the other. The likelihood of catching that potential cheating spouse with a lover is very, very high," Mesis said.
"It's the best time to catch a cheat -- even mistresses and girlfriends expect Valentine's Day," said one person who asked to be left anonymous.
One New York couple had different opinions when they were asked their thoughts about hiring a private investigator to stake out a spouse.
"I actually think it's ridiculous, because that means there is no trust in that relationship," the husband said.
His wife, however, didn't agree.
"But sometimes you need to check up, so maybe it's a good idea," she said.
While many people went out buying chocolate and flowers for this holiday, some were shopping for spyware. At Brickhouse Security in New York, employees say February sales have more than doubled this year.
"It's so easy to become your own detective right now," Brickhouse Security CEO Todd Morris said.
The perfect anti-Valentine's Day gift is a device that tells you who your significant other has been calling and texting. There is also a keyboard logger that exposes e-mails, even ones that are deleted.
One of the most common lies involves where someone is going. The piece of spyware to get the truth about that is the GPS tracker. All you have to do is hide it in your spouse's car, bring up the map and it will tell you exactly where they are.
Whether you choose to ambush them is a completely different story.
"Hopefully, they're finding out their fears are unfounded, and if not, they're at least finding out that they really know the truth," Morris said.
So be warned: Cupid may not be the only one who has you in his sights this Valentine's Day.