A former member of the Special Forces, Wade Wilson ( Ryan Reynolds) works as a heavy for hire – taking down bad guys for a price. When Wilson meets local call girl, Vanessa Carlysle ( Morena Baccarin) , his life is forever changed and the pair enjoy a fairytale ( albeit depraved) romance – until Wilson discovers that late-stage cancer has spread to his liver, lungs, prostate, and brain.
Determined to prevent Vanessa from watching him wither away, Wilson agrees to undergo an experimental procedure – which he is told will cure his cancer by unlocking dormant mutant abilities.