Man vs. Machine vs. Machine
"Computer becomes sentient, attacks humans" is hardly a novel storyline, but recent seasons of CBS' initially routine police procedural Person of Interest breathed life into the formula. The series also presents countless examples of the folly of letting government sacrifice liberty for security.
"The Machine"—a surveillance program initially designed to help intelligence agencies prevent terrorist attacks—isn't as flashy as Skynet or HAL 9000. Instead, it transmits cryptic codes and instructions to the protagonists, for whom it feels increasingly human affection.
Then a rival program, "Samaritan," comes online. Samaritan classifies all people as either assets or threats to its existence. The heroes eventually accept that it can't be beaten—the best they can do is hide by creating a glitch that causes Samaritan to mislabel them.
A showdown between Samaritan and the Machine is inevitable. One character, a vigilante hacker, asks, "Do you really want to see two gods go to war?" Who wouldn't?