|Headquarters/Base||Pairs, Moscow, Area 51, Fort Knox|
|Leader(s)||Vikram Kabra and Isabel Kabra|
|Goal||Collect the 39 Clues before the other branches|
|Enemies||Tomas, Janus, Ekaterina, Madrigal branches, Nellie Gomez|
Luke Cahill was the oldest child of Gideon and Olivia Cahill. As he was the oldest, the Lucian branch was the first Cahill branch. After a fire burnt down Gideon's house, killing him, Luke decided to take off on his own with his 39 Clues, hurt by accusations by his siblings. Soon, Luke became the founder of the Lucian branch, the most conniving and sneaky branch. They found new ways to hide their Clues, and became masters of sneaky tactics. They hid clues to be sent around the world to hidden strongholds everywhere. However, Benjamin Franklin didn't trust his Lucian brothers, so he hid one Clue, Iron Solute, in Paris without referring to his fellow Lucian.
Lucian Gustav Eiffel was given 10 million franks to construct hiding places for Blood, a key Clue. He built the Eiffel Tower and the Statue of Liberty and the Lucians moved the vial of Blood between both landmarks, confusing other Cahills. The Amber Room was stolen and rebuilt under the Church on the Blood containing Lucian files, and a clock containing Amber, a Clue. The Black Circle was created to protect the Amber Room from Cahills. Clover, a Clue was hidden by the Lucian government in Fort Knox with Gold (unknowingly another Clue), the Magna Carta, and the Crown of St. Stephen to throw other Cahills off the track.
The Lucian leadership was given to Vikram Kabra, and his wife Isabel. Even though they were retired, they continued to rule the Lucians with an iron fist, and were able to bribe every cop worldwide to effectively control the government. When Grace Cahills death prompted the renewed hunt for the 39 Clues, the Lucians sent out Irina Spasky, Ian Kabra, and Natalie Kabra to hunt for Clues. Irina was killed saving Amy Cahill, Dan Cahill, and Alistair Oh. Also frustrated with her children's failures, Isabel joing Ian and Natalie in the Clue hunt, although her tactics slightly bothered her children as being too fierce.
Isabel Kabra Ian Kabra Natalie Kabra Irina Spasky Ana Flores Chrissy Collins Andras Gergely
|Current and Historical||Ana Flores | Benjamin Franklin | Ching Shih | Chrissy Collins | Gordon Klose | Irina Spasky | Isaac Newton | Isabel Kabra | Linda Sue Park | Luke Cahill | Patrick Carman | Sidney George Reilly | Vikram Kabra (Leader)|
|Defected||Ian Kabra | Natalie Kabra|
|see all Cahills|