The Day the World Went Away (Person of Interest)

"The Day the World Went Away" is the 10th episode of the fifth season of the American television drama series Person of Interest. It is the 100th overall episode of the series and is written by Andy Callahan and co-executive producer Melissa Scrivner Love and directed by Frederick E. O. Toye. It aired on CBS in the United States and on CTV in Canada on May 31, 2016.

The series revolves around a computer program for the federal government known as "The Machine" that is capable of collating all sources of information to predict terrorist acts and to identify people planning them. A team follows "irrelevant" crimes: lesser level of priority for the government. However, their security and safety is put in danger following the activation of a new program named Samaritan. In the episode, Finch's cover is blown and the team tries to protect him while the war against Samaritan escalates. The episodes features the deaths of Carl Elias and Samantha "Root" Groves, who appeared in the show since the first season. The episode is named after Nine Inch Nails' song of the same name from the 1999 album The Fragile, the song also features at the end of the episode.

According to Nielsen Media Research, the episode was seen by an estimated 6.66 million household viewers and gained a 1.0/4 ratings share among adults aged 18–49. The episode received universal acclaim from critics, who praised the writing, directing, action, acting, twists and emotional impact. The scene where Finch provides a soliloquy received particular praise, with many deeming it one of the show's greatest moments.