The synthesis, morphological characterization, and deformation behavior of a triblock copolymer containing linear polyethylene (LPE) end blocks and a hydrogenated polyhexylnorbornene (hPHN) midblock are presented. The block copolymer forms a homogeneous melt; upon cooling, LPE crystallization creates a lamellar structure consisting of alternating "hard" semicrystalline LPE domains and "soft" rubbery hPHN domains, imparting thermoplastic elastomer (TPE) behavior to the material. At 20 wt % LPE, the triblock shows a low modulus, high ultimate strain, and excellent strain recovery compared with other crystalline-block TPEs. Though the LPE crystals fragment upon deformation, the interposing hPHN layers hinder I-PE fragments originating in different layers from fusing together, preserving the memory of the original domain morphology to high strains.