With Princess Illiana on board, the Independence begins its mission into the currents, but soon encounter Grey forces as they abduct citizens of an inhabited planet within the Briar Patch. Examining an abductee, Cole and her crew find evidence that suggests that the Grey have been a threat to the Federation for longer than previously realized. The Excelsior gives chase to a Breen vessel they believe may be carrying the fugitive Vorina. Henglaar and Qu'Qul prepare for their holodeck showdown, despite Sou’s objections.

While exploring the currents in the Briar Patch, the Excelsior crew realize the Tholians have a greater presence in the patch than previously thought. An ambush on a planet surface leaves Barrett racked with guilt and it's up to his friends and colleagues to rally round him. Meanwhile, a diplomatic conference with the Tholian Ambassador raises more questons than answers.

The Federation considers using Centris III as a listening post. The planet is believed to be uninhabited and offers a perfect chance for some well-deserved shore leave. "The Camping Trip Mission" begins and Barrett, Ro and Aster get more than they bargained for. The camping trip becomes a life and death battle for one of the team.

While the Excelsior attempts to lend assistance to a longtime member of the Federation, Security Chief Matt McCabe finds develops suspicions that do not endear him to the world’s rulers. He grows close to a local security officer while they investigate the supposed terrorist activities that the planet is suffering from. Soon, they stumble onto something far more dangerous.

Captain Shelby experiences a personal loss, while the rest of Excelsior’s crew uncovers some of the secrets of the Grey. Naros history with Tren'La make working with Princess Illiana difficult, as they discover more clues that link the Grey with the tetrahedrons.

Knapp and Naros lead the Antietam on a surveillance mission that gets out of control, while Zen and Aster's relationship is threatened by someone from the Trill's past.