Framed for a crime he didn't commit, Carl Lukas is sent to Seagate prison to serve his sentence. He later escapes after an experiment turns him into a super powered man with bulletproof skin. He assumes a new name of Luke Cage and heads to New York to start a new life.
Luke Cage gets caught up with a criminal gangbanger and works to help protect the people of Harlem from them. Along the way, we discover who framed Luke Cage and how he became the man he did.
The experiments are mentioned more in depth towards the end of the series and describe how Cage got his powers.
The scientist behind the program at Seagate prison (Noah Burstein) mentions Cage to be a "fountain of youth" hinting that the result of the experiments has created a human with enhanced longevity as well as his super strength and bullet-proof skin.
Burstein also mentions his work could now lead to cures for both HIV and cancer.