“Friends” fans have seen the 6 main characters do some pretty stupid things throughout the show’s ten seasons, with many of them involving outright lies. Each of the group’s friends lied at some point, but some lied more than others. Monica Geller (Courteney Cox) was the most honest of all the friends, except when she pretended she wasn’t in a relationship with Chandler Bing (Lisa Kudrow).

Ross was prone to lying, whether small white lies or massive deception. Chandler, Joey Tribbiani, and Ross Geller all lied a lot on the show. But the latter has the worst track record. When Joey and Rachel Green (Jennifer Aniston) were dating. We saw Ross lie about being “fine,” and we saw him cheat on Rachel during their “break.” Ross’s infidelity was one of his worst moments. But it wasn’t the worst lie he’d ever told.

Ross’s biggest lie had a significant impact on Rachel.

Ross had his share of lies, and when you add them all up, you’ll be surprised how often he lied. But his worst lie on “Friends” happened in Season 6, Episode 1 — and it’s pretty bad.

Ross and Rachel tie the knot drunkenly in Las Vegas in the Season 5 finale episode; the Season 6 premiere, aptly titled “The One After Vegas,” deals with the aftermath. Ross tries to persuade Rachel to stay married to avoid another failed marriage to add to the two that have already died, but she rightfully refuses. He then claims that their marriage will be annulled, leading Rachel to believe he will, but Ross does not.

While Ross has committed some heinous acts, lying to Rachel about their annulment is at the top of his list. This is not only immoral, but it also has legal ramifications that could have been disastrous for Rachel if she had been unaware of the situation. After Monica and Chandler marry, Ross even lets her move into his apartment, furthering his deception. Rachel, thankfully, discovers Ross’ deception in Season 6, Episode 4 (“The One Where Joey Loses His Insurance”), and she completely loses it on him while he’s giving a lecture.

Because they don’t qualify for an annulment, the couple gets divorced. Ross and Rachel sign their divorce papers at the end of the episode. Which leads to a tense scene in which Ross inadvertently admits — without saying it. That he is still married to Rachel because he loves her.