In 1936, Boris Karloff and Marguerite Churchill starred in the first film incarnation of the Walking Dead. It was the tale of a man unjustly executed and brought back to life by a scientist. Not quite the plot line your used to with AMC's reincarnation of the Walking Dead.
AMC's version is based upon Robert Kirkman and crew's graphic novels called the Walking Dead which were first issued in 2003. The TV show stays pretty close to the graphic novel but there are some differences.
Here are a few: