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The working mechanism of conventional light-driven molecular rotary motors, especially Feringa-type motors, contains two photoisomerization steps and two thermal helix inversion steps. Due to the existence of a thermal helix inversion step, both the ability to work at lower temperatures and the rotation speed are limited. In this work, a two-stroke light-driven molecular rotary motor, 2-(1,5-dimethyl-4,5-dihydrocyclopenta[b]pyrrol-6(1H)-ylidene)-1,2-dihydro-3H-pyrrol-3-one (DDPY), is proposed, which is capable of performing unidirectional and repetitive rotation by only two photoisomerization (<i>EP→ZP</i> and <i>ZP→EP</i>) steps. With trajectory surface-hopping simulation at the semi-empirical OM2/MRCI level, the <i>EP</i>→<i>ZP</i> and <i>ZP→EP</i> nonadiabatic dynamics of DDPY were systematically studied at different temperatures. Both <i>EP→ZP</i> and <i>ZP→EP</i> photoisomerizations are on an ultrafast timescale (ca. 200–300 fs). The decay mode of <i>EP</i>→<i>ZP</i> photoisomerization is approximately bi-exponential, while that of <i>ZP→EP</i> photoisomerization is found to be periodic. For <i>EP</i> and <i>ZP</i> isomers of DDPY, after the S<inline-formula><math display="inline" xmlns="http://www.w3.org/1998/Math/MathML"><semantics><msub><mrow></mrow><mn>0</mn></msub></semantics></math></inline-formula>→S<inline-formula><math display="inline" xmlns="http://www.w3.org/1998/Math/MathML"><semantics><msub><mrow></mrow><mn>1</mn></msub></semantics></math></inline-formula> excitation, the dynamical processes of nonadiabatic decay are both followed by twisting about the central C=C double bond and the pyramidalization of the C atom at the stator-axle linkage. The effect of temperature on the nonadiabatic dynamics of <i>EP</i>→<i>ZP</i> and <i>ZP→EP</i> photoisomerizations of DDPY has been systematically investigated. The average lifetimes of the S<inline-formula><math display="inline" xmlns="http://www.w3.org/1998/Math/MathML"><semantics><msub><mrow></mrow><mn>1</mn></msub></semantics></math></inline-formula> excited state and quantum yields for both <i>EP</i>→<i>ZP</i> and <i>ZP→EP</i> photoisomerization are almost temperature-independent, while the corresponding unidirectionality of rotation is significantly increased (e.g., 74% for <i>EP</i>→<i>ZP</i> and 72% for <i>ZP→EP</i> at 300 K <i>vs</i> 100% for <i>EP</i>→<i>ZP</i> and 94% for <i>ZP→EP</i> at 50 K) with lowering the temperature.