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Abstract Cellular solids composed of a network of interconnected pores offer low‐density and high strength‐to‐weight ratio as exemplified by wood, bones, corks, and shells. However, the slender edges and low connectivity of the structs in cellular lattices make them vulnerable to buckle, fracture, or collapse. Here, by taking advantage of the continuity of a thin film that can follow curvatures and dissipate energy, shellular materials are created by dip coating a wireframe of the primitive triply periodic minimal surface (TPMS) with an aqueous solution of lyotropic liquid crystalline graphene oxide (GO)/polymer composites. Regulated by surface tension, GO nanosheets align on the polymer soap film as the stress builds up during drying. When the wireframe mesh density is low, the shellular material is film‐dominated, demonstrating superior mechanical strength (384.30 Nm kg⁻¹) and high specific energy absorption (1.59 kJ kg⁻¹) yet lightweight (equivalent density, 0.063 g cm⁻³), with an energy absorption rate comparable to that of carbon nanotube‐based lattices but a lower equivalent density. The study offers insights into designing lightweight yet high‐strength structural materials that also function as impact energy absorbers. 

Abstract Direct ink writing (DIW) of core‐shell structures allows for patterning hollow or composite structures for shape morphing and color displays. Cholesteric liquid crystal elastomers (CLCEs) with liquid crystal mesogens assembled in a helix superstructure are attractive for generating tunable iridescent structural colors. Here, by fine‐tuning the rheology of the core and shell materials, respectively, this study creates droplets or a continuous filament in the core from the precursors of polydimethylsiloxane (PDMS) or poly(vinyl alcohol), whereas CLCE forms the outer shell. By introducing a dye in the droplets, the skin structures of cephalopods, consisting of chromatophores and iridocytes, are mimicked for enhanced color saturation, lightness, and camouflage. After removal of the core material, a CLCE hollow fiber is obtained, which can switch colors upon mechanical stretching and pneumatic actuation, much like papilla along with iridocytes. Further, liquid crystal mesogens assembled in the bulk of the fiber are in polydomain. Thus, the skin appears opalescent at room temperature, much like how leucophores enhance reflectins. Upon heating above the nematic to isotropic transition temperature, the skin becomes transparent. Lastly, a cephalopod model is constructed, where different parts of the model can change colors independently based on different mechanisms.