  The current observational data imply that the universe would end with a
cosmic doomsday in the holographic dark energy model. However, unfortunately,
the big-rip singularity will ruin the theoretical foundation of the holographic
dark energy scenario. To rescue the holographic scenario of dark energy, we
employ the braneworld cosmology and incorporate the extra-dimension effects
into the holographic theory of dark energy. We find that such a mend could
erase the big-rip singularity and leads to a de Sitter finale for the
holographic cosmos. Therefore, in the holographic dark energy model, the
extra-dimension recipe could heal the world.
