On the tenth anniversary of September 11th, FRONTLINE Producer Michael Kirk teams up with Pulitzer Prize-winning journalist Dana Priest, to investigate the dramatic changes that have reshaped America in the last decade. The program examines the history of the secret side of America's 'war on terror,' and asks how a decade of fighting terrorism has reshaped the country and whether it has made us any safer.

Following the tragedies of September 11, 2001, contemporary artists such as Ahmed Basiony, Thomas Demand, Harun Farocki, Jenny Holzer, Trevor Paglen and Taryn Simon urgently pursued the complicated intersection of freedom, security, secrecy, power and violence. 'Covert operations: Investigating the known unknowns' features 13 international artists who have collected and revealed unreported information on subjects ranging from classified military sites...