By: Shannon Bream

A series of undercover videos has reignited the abortion debate. You can catch up on the latest in this shocking story with "Planned Parenthood: The Hidden Harvest," airing Friday night at 10p ET on Fox News Channel. Please be warned that some of these videos are graphic in nature, and might be disturbing to viewers.

You'll learn about the covert operation that revealed a bustling market in fetal tissue. Most Americans know nothing about the practice, but it involves Planned Parenthood and others providing the raw material, which is bought by middlemen who mark up the price and sell it to researchers. It's led Americans to ask themselves if we should be harvesting aborted fetuses this way. And whether all Americans, in the form of tax dollars to Planned Parenthood, should be underwriting it.

The Center For Medical Progress, the activist group that pulled off this sting, claims it caught members of Planned Parenthood in the act of selling baby parts. Planned Parenthood admits it transfers fetal body parts for a price, but says it violated no laws. This is a grey area, as federal law prohibits the sale of fetal remains for commercial gain, but allows payment to reimburse costs. Federal law also bans manipulating abortions to harvest specific parts. Have Planned Parenthood and those it does business with skated up to the edge of the law, or have they crossed the line? Tune in Friday night and judge for yourself.

We'll also be looking at how this story dropped a bombshell into the presidential race. For instance, Democratic front-runner Hillary Clinton at first called the videos "disturbing," but now stands foursquare with Planned Parenthood. Meanwhile, many Republicans candidates call for defunding Planned Parenthood, and at present four House committees and at least a dozen states are launching investigations into the controversy.

Not that all the bashing is of Planned Parenthood. Some claim the Center For Medical Progress has deceptively edited its videos, and the organization is engaged in multiple legal fights as well as facing the prospect of an investigation by California's Democratic Attorney General Kamala Harris.

On Friday, we'll lay out the facts for you. "Planned Parenthood: The Hidden Harvest" is guaranteed to spark a conversation. I hope you'll join us.

Tune in to "Fox News Reporting: Planned Parenthood: The Hidden Harvest" tonight at 10p ET on Fox News Channel.

WARNING: The video below contains graphic content which may be disturbing to viewers.

Catch up on the Planned Parenthood controversy:

Former Planned Parenthood Employee: Harvesting Fetal Body Parts Is 'Big Business'

Activist Who Exposed Planned Parenthood: There Will Be a Total of 12 Videos

Disturbing New Planned Parenthood Video Details Harvesting Fetal Body Parts