Ten years ago, Carter Wright was accused of starting a fire that killed his ex-wife. He's been on death row ever since. When LGB gets a cryptic call about the case from a courthouse clerk, they realize that something must have been overlooked by his previous counsel and they have less than 8 hours before the deadline to file an appeal.
Since our team doesn't know if the tip came from the clerk or the judge, they must dig into the lives of both in order to find clues. The judge, we learn, has just married a woman who is liberal and anti death penalty. The clerk has written specialized briefs on scientific and forensic evidence.
With Cary temporarily back on our side after some strong-arming by the Innocence Project via Kalinda's insistence, the team pursues every angle it can think of. They track down an alternate suspect - a business rival of Caroline's ex - but not only has did he die three years earlier, his wife can provide an alibi. They also try to delay the execution because the state's supply of anesthetic expired. While Will fights in court, the prison attempts to secure a fresh supply from other nearby prisons.
The case turns when Kalinda tracks down the old arson investigator as he is about to get on a plane and gets him to write an affidavit stating that his previous testimony was wrong: modern arson science shows that this fire may have been accidental. This is good enough for the judge to order a stay of execution.
In the end, they are able to free Carter pending his appeal. He is reunited with his daughter, Ruby, whom Diane had spent the entire episode trying to help get into death row in order to see her dad one last time before the execution.
While Alicia fights to save Caroline's life, Peter participates in the first debate against Glenn and Wendy. When an audience member goes rogue and quizzes Peter on Alicia's possible relationship with Will, Peter vehemently defends his wife and storms off the stage in disgust. Has he just harpooned his campaign, or has his emotional outburst helped humanize him?