At the start of the series, Peter is an FBI agent who works a lowly job in a windowless room in the White House basement: answering the Night Action phone line and connecting the caller to a night agent.

Night Action is a top-secret investigative program within the FBI, usually involving matters of national security. Most times, the phone never rings and Peter passes the time analyzing confidential reports. But Peter springs into action when a woman named Rose calls Night Action just before her aunt Emma (Simone Kessell) and uncle Henry Campbell (William MacDonald) are hunted down and killed by two assassins.

Rose soon learns that her relatives were actually spies who worked in counterintelligence. Peter is then tasked with protecting Rose, whose life is in danger because she caught a glimpse of one of the assassins' faces. On top of that, Rose overheard her aunt and uncle discussing an investigation into a mole in the White House and something significant set to happen in a few days.

As Peter and Rose go on the run together, unsure of who to trust besides each other, they become closer and strike up a romance.

Eleven years prior to the start of season one of "The Night Agent," Peter Sr. was accused of leaking classified documents that comprised US defense strategies. The breach was traced back to the FBI's counterintelligence division, where his dad was the section chief.

Peter Sr. died in a car crash before he could be charged and was branded as a disgraced intelligence officer. Peter Jr. was a teenager at the time.

In the finale, Peter gets access to his dad's confession tape and finally gets the answers he's been searching for.

He learns that in 2004, Peter Sr. was approached by a foreign agent seeking to undermine American interests. Peter Sr. accepted payment in exchange for information on private contractors, which ultimately led to a breach at the Pentagon.

The confession tape confirms what Peter had suspected all along but hoped wasn't true: his dad was a traitor.

However, there's more to the story. Peter Sr. agreed to work as a double agent for the US in an effort to rectify his error. To stop him from helping the administration, a foreign assassin killed Peter Sr. in a car crash.

Although the public will never know the truth about Peter Sr., Peter gets closure and makes peace with his dad's actions.

"The Night Agent" begins with Peter, who's working for the FBI, saving a train full of people from a bombing on the DC metro a year earlier.

When he notices a suspicious person putting a backpack on the train and finds a bomb inside, Peter pulls the emergency brake and instructs the civilians to exit via the tunnels. He manages to get everyone off the train just as the explosion happens. Although Peter was a hero, he's publicly accused of being behind the metro bombing and vilified, the same way his father was.

Following the incident, Peter accepts a deal to pay his dues and manage the Night Action line until he earns a promotion.

As the season unfolds, it's revealed that Redfield (Christopher Shyer) and Wick (Ben Cotton) orchestrated the bombing.

Their target was Omar Zadar (Adam Tsekhman), a Balkan dissident and leader of the People's Independence Front (PIF). Redfield and Wick attempted to assassinate Zadar via the bomb while he was in the US for a meeting. But because Peter detected the bomb early on the train route, it never made it to its intended destination and Redfield and Wick had to figure out a way to cover up the bombing.

Rose's aunt and uncle were murdered by assassins hired by Wick because they were getting too close to finding out the truth about the metro bombing.

Peter reports to two people, Diane Farr (Hong Chau), the White House Chief of Staff, and Jamie Hawkins (Robert Patrick), deputy director of the FBI. Although Peter's career was impeded by what his dad was accused of doing, Farr never judged him based on that. When Rose suggests that Farr could be the White House mole, Peter finds it difficult to accept because he trusts Farr.

But in episode six, Peter has a strange interaction with Farr and realizes that she's connected to the metro bombing.

In a flashback during episode nine, it's revealed that on the day of the bombing, Farr was unwillingly brought in to work with Wick and Redfield and hide their involvement because if Redfield was found to be part of the investigation, it would reflect badly on Farr, President Travers, and the whole administration.

As part of the coverup, Farr chose Peter for Night Action because she planned on using him as the fall guy in case things went sideways.

In the finale, Farr gets shot but survives. Rose then tells her that she's sparing her life, and looks forward to Farr clearing Peter's name and getting sent to prison.

To cover up their involvement in the bombing, Redfield and Wick again attempt to assassinate Zadar — plus President Michelle Travers (Kari Matchett) — at a last-minute meeting at Camp David during the finale.

Peter, Rose, and Secret Service agent Chelsea Arrington (Fola Evans-Akingbola) team up to locate the bomb at Camp David and protect POTUS. They narrowly avoid getting in the crosshairs of a bomb, but Redfield and Wick have a contingency plan in place, and pivot to an armed bomb that's on the president's helicopter, Marine One.

When Peter gets a hold of President Travers, he tells her that there's a bomb on the helicopter and that Redfield is trying to kill her. The bomb goes off inside Marine One, but Travers is unscathed thanks to Peter stopping her from getting on the helicopter.

After order is restored, President Travers tells Peter that the Night Action program runs deeper than he can imagine. As a reward for his heroic actions at Camp David, she offers him a job as a night agent.

Then, Peter kisses Rose and says goodbye before boarding a US Air Force plane. Rose tells Peter she won't forget him, and he promises to call her when he can. Once the plane takes off and clears American airspace, Peter unlocks a tablet containing his first Night Action mission briefing.

While Peter is headed to an undisclosed location, the finale doesn't indicate where exactly Rose is going. However, during episode nine, Rose tells Peter that when everything is over, she'd like to return to California and try again in the tech space after learning from her past mistakes.