In this article we describe for bimesogens the first observed transition from a “heliconical” twist-bend nematic liquid crystal to a novel biaxial, anticlinic, intercalated lamellar phase. The phase behaviour and structures of both polymorphs is similar to that of polymers, confirming that bimesogens can act as model systems for main chain liquid crystal polymers, and in principle are separate soft-matter branches of self-organising systems.