Complete story — includes the ending
The team go to install software at the stock exchange that will stabilize the market. However, they are almost immediately intercepted by Samaritan operatives, who corner them in a room. Out of options, the team turns to The Machine, who in a matter of seconds provides a multitude of projections and outcomes in each. While doing so, it reflects on multiple chess matches it played and the lessons it learned with Finch in 2003. In a final simulation, The Machine projects a roughly 2% chance of survival and instructs the team to follow it. Shaw is stuck on a subway train with a stock market exchange manager with a security code to the exchange's server room. However, she is interrupted by a would-be suicide bomber who she kills in the first two simulations (and thus gets herself arrested) but talks down in the final and ultimate outcome. After sending the code to Root, she arrives as the two teams clash, opting to hold the Samaritan operatives off as Finch, Reese, Fusco, and Root escape. She traps them in the elevator, but Martine shoots Shaw multiple times before approaching her as the elevator doors slam to a close.
Sources and content license
Source and revision history · Adapted from Wikipedia contributors, Person of Interest season 4. HTML formatting and reference markers removed. · Content license