What Lies Beneath is the twenty-sixth episode of Slugterra. It aired in Canada on July 1, 2012.
When Eli and the Shane Gang find themselves trapped in the Deep Caverns underneath Slugterra they discover a whole new type of danger threatening to escape. Allowing it past the barrier would mean unprecedented peril — not only for Slugterra, but our world above too!
- Eli Shane
- Kord Zane
- Dr. Blakk
- John Bull
- El Diablos Nacho
- Shadow Clan
- Featured slugs: Boon Doc, Darkfurnus, Guardian Slugs
- This is the first time the Shane Gang resorts to using ghouls.
- In this episode, Doc leaves the team to become a Guardian Slug.
- The chair built by The Shanes as seen in The Great Abyss is similar to the one in The Drop as seen in "The World Beneath Our Feet Part 1" and "A Distant Shore".
- The Shadow Talker is seen and used again after Eli gets it from his father's chest in "Inheritance", but this time Eli is able to handle its effects.
- El Diablos Nacho returns after a long absence since "The New Kid Part 2".
- But while in the Deep Caverns, unknown to the Shane Gang, Nacho also whispers his past encounters with the gang and Eli's identity as a Shane to Brimstone.
- Brimstone references his past encounters with "Midlanders" (aka non-Darkbane) and the Shanes, probably hinting at his past encounters with Dr. Blakk and with Will Shane who had been defeated in The World Beneath Our Feet Part 1.