A photomechanical system using a liquid-crystal network with azobenzene chromophores can be bent in any direction by linearly polarized light. This effect is due to photoselective volume contraction and can be used for high-speed actuators in micro- and nanoscale applications, such as microrobots or optical tweezers. The films were prepared by thermal polymerization of a liquid-crystal monomer and a diacrylate crosslinker, both containing azobenzene. When exposed to 366-nm polarized light, the film bends in the direction of the light polarization, and can be flattened again with visible light over 540 nm. Changing the polarization direction of the light alters the bending direction of the film. The bending-unbending cycle can be repeated without fatigue, showing precise control over the film's bending direction. The film's bending is due to the trans-cis isomerization of azobenzene moieties aligned with the light polarization. This results in a macroscopic volume contraction and bending of the film. The system can be miniaturized for use in driving micromachines and nanomachines without batteries, motors, or gears, using remote laser irradiation. The study shows the potential of this photomechanical system for various applications. The research was conducted by Yanlei Yu, Makoto Nakano, and Tomiki Ikeda at the Chemical Resources Laboratory, Tokyo Institute of Technology. The study is supported by references to previous works on photomechanical effects and liquid-crystal materials. Supplementary information is available on Nature's website.A photomechanical system using a liquid-crystal network with azobenzene chromophores can be bent in any direction by linearly polarized light. This effect is due to photoselective volume contraction and can be used for high-speed actuators in micro- and nanoscale applications, such as microrobots or optical tweezers. The films were prepared by thermal polymerization of a liquid-crystal monomer and a diacrylate crosslinker, both containing azobenzene. When exposed to 366-nm polarized light, the film bends in the direction of the light polarization, and can be flattened again with visible light over 540 nm. Changing the polarization direction of the light alters the bending direction of the film. The bending-unbending cycle can be repeated without fatigue, showing precise control over the film's bending direction. The film's bending is due to the trans-cis isomerization of azobenzene moieties aligned with the light polarization. This results in a macroscopic volume contraction and bending of the film. The system can be miniaturized for use in driving micromachines and nanomachines without batteries, motors, or gears, using remote laser irradiation. The study shows the potential of this photomechanical system for various applications. The research was conducted by Yanlei Yu, Makoto Nakano, and Tomiki Ikeda at the Chemical Resources Laboratory, Tokyo Institute of Technology. The study is supported by references to previous works on photomechanical effects and liquid-crystal materials. Supplementary information is available on Nature's website.