  We revisit the simplest model for dark matter. In this context the dark
matter candidate is a real scalar field which interacts with the Standard Model
particles through the Higgs portal. We discuss the relic density constraints as
well as the predictions for direct and indirect detection. The final state
radiation processes are investigated in order to understand the visibility of
the gamma lines from dark matter annihilation. We find two regions where one
could observe the gamma lines at gamma-ray telescopes. We point out that the
region where the dark matter mass is between 92 and 300 GeV can be tested in
the near future at direct and indirect detection experiments.
