Off the coast of Malibu, sonar imagery captured in 2014 by ocean-floor mappers revealed a large, flattened oval formation 600 m below the surface, sparking theories of an underwater UFO (USO) base. Video analyst Jimmy Church and SecureTeam 10 popularised the claim after identifying what appeared to be “pillars” supporting a domed roof 2.5 miles wide. Marine geologists later concluded the shape is a natural sediment ridge, yet divers and boaters still report strange orbs rising from the water and electronic interference near the site. The mystery endures as one of California’s best-known ocean anomalies.