 The show was filmed at a number of locations across San Diego including aboard the and the , which stands in for the show's fictional USS "Nathan James" (DDG-151).A second season (of 13 episodes) was ordered in 2014 and aired in 2015, and a third season (also of 13 episodes) was ordered in 2015 and aired in 2016.A fourth season of 10 episodes aired in August 2017 and a 10 episode fifth and final season aired in September 2018.