Octavia Blake is a fictional character from the television series The 100, which is based on the book series by Kass Morgan. She is portrayed by actress Marie Avgeropoulos and is known for her strong and resilient personality. Octavia is the younger sister of Bellamy Blake and grows up in a confined space on a space station called The Ark before descending to Earth. Throughout the series, Octavia evolves from a sheltered girl into a fierce warrior. She becomes a key figure in the struggle for survival among the various factions on Earth, including the Grounders and the Sky People. Her journey explores themes of identity, freedom, and the consequences of violence.