One of the biggest secrets in Port Charles history is set to be exposed at what was supposed to be a joyous occasion, but will instead become a night no one will forget on General Hospital.

Nikolas And Britt's Surprising Engagement Party

Everyone has gathered to celebrate Nikolas (Tyler Christopher) and Britt's (Kelly Thiebaud) engagement, but Britt's huge secret about her son, Ben, will be exposed to everyone present.

In a preview clip for the Friday, March 21 episode, the evidence that proves Britt has been lying about being Ben's mother will continue to stack up against her.

Britt Considers Telling Nikolas The Truth About Baby Ben?

"This letter's going to change everything," Elizabeth (Rebecca Herbst) said to Ric (Rick Hearst) as the two began to digest the evidence they found while snooping around in the Cassadine mansion.

Britt had previously thought she destroyed all the evidence that she wasn't Ben's mother, but had missed what Elizabeth and Ric found. The two could use the letter to expose her.

Even without their evidence however, several people are questioning why Ben doesn't look anything like his supposed mother, including his biological mother, Lulu (Emmee Rylan).

"Why do you look like me?" she asked the baby in the preview clip.

The truth about Lulu's husband, Dante (Dominic Zamprogna) being the baby's father was already revealed by a DNA test, but both and he and Britt have dark hair, while Ben possesses the fairer features that Lulu has.

If the truth about Britt's lies do come out, not only will she likely lose custody of Ben, but she could see her fiancé walk out the door as well, because her lies made him believe Ben would only be his stepson, when in reality he is his nephew.

General Hospital airs Monday-Friday at 2 p.m. on ABC.

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