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1. Beyond the Underground by mallory8367

   Fandoms: Teenage Mutant Ninja Turtles - All Media Types, Teenage Mutant Ninja Turtles (Bay Movies)  

   • Not Rated
   • Creator Chose Not To Use Archive Warnings
   • F/M
   • Work in Progress

   17 Jul 2026

   Tags

   • Creator Chose Not To Use Archive Warnings
   • Leonardo (TMNT)/Original Female Character(s)
   • Michelangelo (TMNT)/Original Female Character(s)
   • Leonardo (TMNT)
   • Michelangelo (TMNT)
   • Donatello (TMNT)
   • Raphael (TMNT)
   • April O'Neil (TMNT)
   • Casey Jones (TMNT)
   • Splinter (TMNT)
   • The Foot Clan (TMNT)
   • Tiger Claw (TMNT)
   • Shredder Tengu (TMNT)
   • Foot Soldiers (TMNT)
   • Original Female Character(s)
   • Original Characters
   • Hurt Leonardo (TMNT)
   • Good Sibling Michelangelo (TMNT)
   • Protective Raphael (TMNT)
   • Protective Leonardo (TMNT)
   • Good Sibling Raphael (TMNT)
   • Good Sibling Leonardo (TMNT)
   • Good Sibling Donatello (TMNT)
   • Hurt Michelangelo (TMNT)
   • Conspiracy
   • Investigations
   • Biology
   • Crime Fighting
   • Kidnapping
   • Michelangelo Needs a Hug (TMNT)
   • Protective Michelangelo (TMNT)
   • BAMF Michelangelo (TMNT)
   • Romance
   • Meet-Cute
   • Awkward Flirting
   • Falling In Love
   • Friendship/Love
   • Science Experiments
   • Mutation
   • Mind Manipulation
   • Height Differences
   • Aged-Up Character(s)
   • Hurt/Comfort
   • Trauma
   • Medical Trauma
   • Healing
   • Protectiveness
   • Protective Siblings

   Summary

   Jules is gone, and Leonardo refuses to stop searching.

   Driven by desperation, the turtles follow every lead they can find, only to uncover a conspiracy that stretches far beyond Helix Dynamics. Along the way, an unexpected ally joins their fight, bringing new hope—and dangerous new questions.

   While her family searches above, Jules is trapped below, where every day pushes her closer to becoming something she was never meant to be.

    

   Somewhere beyond the underground, the truth is waiting.

   Series

   • Part 3 of The Underground Chronicles

   Language:

   English

   Words:

   7,725

   Chapters:

   4/?

   Comments:

   9

   Kudos:

   11

   Bookmarks:

   2

   Hits:

   196