The paper explores a novel mechanism for decoupling WIMP dark matter from the Standard Model (SM) through the annihilation of WIMPs into metastable mediators, followed by delayed decay to SM states. This mechanism allows WIMPs to remain secluded from the SM with a very small elastic scattering cross-section on nuclei and a low rate for direct collider production. However, indirect signatures from WIMP annihilation, such as $\gamma$-ray signals, can still be detectable. The authors construct explicit models with fermionic, scalar, and vector mediators, demonstrating that if the WIMP mass is greater than the mediator's mass, the secluded WIMP models can be highly constrained by indirect signatures but not by direct or collider searches. They also discuss the implications for MeV-scale dark matter, which could potentially explain the 511 keV line observed from the galactic center. The paper concludes by highlighting the complementarity of direct and indirect detection efforts for WIMP dark matter.The paper explores a novel mechanism for decoupling WIMP dark matter from the Standard Model (SM) through the annihilation of WIMPs into metastable mediators, followed by delayed decay to SM states. This mechanism allows WIMPs to remain secluded from the SM with a very small elastic scattering cross-section on nuclei and a low rate for direct collider production. However, indirect signatures from WIMP annihilation, such as $\gamma$-ray signals, can still be detectable. The authors construct explicit models with fermionic, scalar, and vector mediators, demonstrating that if the WIMP mass is greater than the mediator's mass, the secluded WIMP models can be highly constrained by indirect signatures but not by direct or collider searches. They also discuss the implications for MeV-scale dark matter, which could potentially explain the 511 keV line observed from the galactic center. The paper concludes by highlighting the complementarity of direct and indirect detection efforts for WIMP dark matter.