Rick Deckard is a veteran Blade Runner and fugitive appearing in Ridley Scott's 1982 film, Blade Runner and Denis Villeneuve's 2017 sequel Blade Runner 2049. The character originally appeared in Philip K. Dick's novel, "Do Androids Dream of Electric Sheep?" on which the movie is based. Rick Deckard is played by Harrison Ford.
A Blade Runner is a special member of the L.A. Police Department who is employed to hunt down and "retire" replicants (genetically manufactured humanoids). Since they were declared illegal on Earth, it is up to the Blade Runners to "retire" any that find their way to Earth.