Jason Atwood was the former Deputy Director of the FBI. He initially aided his colleague, Hannah Wells in her investigation into the Capitol bombing, until his son, Luke, was kidnapped and held hostage by an unknown female conspirator. Under instructions from her in order to ensure Luke's safety, he falsely confessed to the murder of the Al-Sakar leader, Majid Nassar and was imprisoned. He was released from custody, but he was fired. He began directly aiding Hannah in her investigation into the conspiracy once Luke's killer was identified. However, Jason was caught spying on top conspirators Jay Whitaker and Patrick Lloyd and was shot by Nestor Lozano.
Just moments after the Capitol exploded, Jason was presented by Hannah Wells with the theory that the perpetrators responsible did not claim credit because they were not finished with whatever they were doing. However, when President Kirkman asked him for any suspects, Jason stated that they primarily suspected Al-Sakar. When Hannah confronted him for not telling the President about her theory, he replied that if she wanted him to, she had to prove it.
Jason did not get directly involved with Hannah's investigation until she showed him the existence of Room 105; a secret bomb shelter Congressman Peter MacLeish was hiding in during the attack. He went to report the discovery to President Kirkman, but due to MacLeish's sudden presence, he simply told that they were making progress.
After Majid Nassar was apprehended, Jason, along with Hannah interrogated him. They both discovered that he was set up to claim responsibility for the attack by a man called "Catalan". Unfortunately, that was all the information they got from him, because Nassar was assassinated hours after.
On a later evening, Jason was confronted by a mysterious woman who had Luke hostage. Jason drew out a gun and demanded Luke's location, only to put away the gun after she told that Luke would die if she was harmed. He was handed a phone to await further instructions from the woman.