Time travel is the beating heart of Starz's Outlander but within the world of the series it remains one of Claire Fraser’s most dangerous truths. Claire’s accidental journey from 1945 to the 18th century through the standing stones at Craigh na Dun forces her to live a double life.In a time shaped by superstition and war, the idea of a woman traveling through centuries is not just unbelievable but potentially fatal, which is why Claire guards her secret fiercely, revealing it only when trust or necessity leaves her no other choice. From her soulmate Jamie Fraser to family members and friends, every person entrusted with Claire’s secret plays a crucial role in the unfolding saga of Outlander. Here’s a closer look at every major character in Outlander who knows Claire’s time-traveling secret.Here's a list of every major character who knows Claire's time-traveling secret in Outlander View this post on Instagram Instagram PostJamie FraserJamie Fraser was one of the first characters from the 18th century who learned about Claire's time-traveling secret in Outlander Season 1. After the couple was married under difficult circumstances and developed a genuine bond, Claire confided in her husband. While Claire feared Jamie's reaction, he instantly believed her and even took her back to the Craigh Na Dun stones. However, since Claire had also fallen in love with the Highlander by this time, she chose to stay in the past.This moment remains one of the most iconic from the series, where Jamie unburdened Claire of this long-held secret, laying the foundation for their perfect partnership in the series.Geillis DuncanAs a fellow time traveler, Geillis Duncan was a little too interested in Claire when she first arrived at Castle Leoch and met her. While Geillis constantly probed Claire for more information, she finally learned the truth about her time-traveling abilities during the witch trials from Outlander Season 1.This was a shocking moment for our time-traveling heroine as well, as she learned that Geillis is also a time traveler, after she revealed her smallpox vaccination scar as the 'Devil's mark.'Murtagh FitzgibbonsOutlander fans were waiting for Murtagh to discover Claire's secret for a long time, and the moment finally came in Season 2, when the couple traveled to France. While Murtagh was already suspicious of Claire's strange knowledge and magical healing abilities, he learned the truth from Jamie.Like Jamie, his Godfather also had a wholesome reaction to Claire's secret. While he was naturally taken aback and confused at first, he eventually comforted Claire, cementing the trio's shared camaraderie, trust and respect even further.Roger and Brianna MacKenzieBrianna MacKenzie in the Starz series (Image via Instagram/@outlander_starz)As a fellow time traveler like her mother, Brianna learns about her mother's time-traveling abilities in the 20th century. While she loved Frank as her father, she encouraged Claire to take another time-traveling trip and reunite with her true love. Later, when Brianna came across Claire and Jamie's obituary in a newspaper, she embarked on her own adventure to the past, which reunited her with Claire and Jamie.Since Roger grew up with Rev. Wakefield, he learned about Claire's time-traveling abilities when he was a little boy. Once he grows up and falls in love with Brianna, he discovers his own time-traveling powers and follows her into the 18th century.Frank RandallFrank was among the few Outlander characters from the 20th century who knew about Claire's time-traveling secret. After his wife disappeared into thin air, he was heartbroken but never stopped searching for her. Frank learned about Claire's adventure when she returned before the Battle of Culloden in the sophomore season.Later, he also found Claire's obituary in an old newspaper from the 1770's, which proved her story. While Frank accepted his wife's story and Jamie's child as his own, the secret eventually ruined his marriage with Claire.Young IanYoung Ian, Jenny and Ian Murray's son, learned about his auntie's time-traveling powers in Outlander Season 5, after he returned from his time with the Mohawk clan. After Young Ian questioned Jamie and Claire about the latter's strange powers and healing abilities, Claire finally revealed her secret to him.Since Young Ian had always been supportive and loving towards his Uncle and Aunt, he had a wholesome reaction to Claire's secret, calling her a 'faery'.Every supporting character who learned about Claire's secretIn addition to these major characters, some supporting/guest characters eventually learned about Claire's secret in Outlander. Here is the complete list:Jenny: Jamie's sister learned about Claire's secret when Ian was on his deathbed. When Claire revealed that she is from the future, Jenny begged her to save her husband.Tewaktenyonh: The Mohawk healer realized that Claire was a time traveler when the Frasers were building their home at Fraser's Ridge.Rev. Wakefield and Mrs. Graham: Mrs. Graham believed in the magic of Craigh Na Dun stones. She and Rev. Wakefield were among the few characters who discovered Claire's secret when she returned to her time in the present.Dr. Abernathy: Claire's friend from the 20th century became her supportive confidante and learned about her abilities when she returned from the past in Outlander Season 2.Outlander will return with its eighth and final season on Starz on March 6.For the latest scoops on your favorite TV shows and movies, follow SoapCentral.