Jessica Logan is the wife of Wyatt Logan.
Jessica Logan was mysteriously murdered in San Diego, California. One night, after an argument with her husband Wyatt Logan, she decided to stay out rather than to head home. According to Wyatt, that was the night that she died. Due to how she decided to stay out because of an argument they had together, Wyatt blamed himself for her death.
Despite his attempts at figuring out what happened to her, the details and circumstances of her murder are unknown. But we do know that there is also a portion of Lucy Preston's diary from the future that has an entry on Jessica Logan in it.
When Wyatt helped Garcia Flynn capture Benedict Arnold, he promised that he'd give Wyatt the name of Jessica's killer. Wyatt then cooperated with Flynn to capture Arnold. Flynn revealed the name of Jessica's killer to be Wes Gilliam, a man serving for the murders of two other women, who was at San Quentin State Prison.
Later, Rufus Carlin and Wyatt steal the Lifeboat to prevent the conception of Wes and therefore prevent the murder of Jessica. Despite Wyatt being successful in preventing the conception of Wes, Jessica continued to remain dead. This implies that Wes was not the true murderer of Jessica.
After the crew succeeds in stopping Rittenhouse from dispensing propaganda in William Randolph Hearst's newspapers, Jessica is inexplicably alive again.
Jessica is less happy to see Wyatt's return than he is to see her, as from her perspective Wyatt simply stopped responding to her text messages for two months, inexplicably. Jessica later reveals that she wants a divorce, claiming he was constantly drunk and unable to change for long. In order to excuse his previous self's actions, Wyatt proves to Jessica time travel's existence, much to the dismay of Agent Denise Christopher. She then begins to stay in the bunker with Wyatt along with the rest of the crew, spending large amounts of time with Wyatt and everyone.
It is later found out that Rittenhouse was behind Jessica's resurrection, but their motives for doing so are unclear. Denise Christopher and Connor Mason then found evidence that suggests Jessica may be more involved with Rittenhouse than they had known previously. They ask Wyatt if there was anything off about Jessica that supported the idea of her being involved with Rittenhouse, but he refused to believe she was a part of it.
After Wyatt returns from his mission to 1981, Jessica reveals she is pregnant.
After Wyatt tells Jessica that Christopher wants her out of the bunker, Jessica kidnaps Jiya and steals the Lifeboat, revealing herself to be a Rittenhouse agent. After delivering Jiya and the Lifeboat to Nicholas Keynes and Carolyn Preston, it becomes clear that her mission was to infiltrate the bunker and then to kill everyone. However, Jessica couldn't bring herself to murder her husband, so she opted to steal their time machine and their pilot instead.
After traveling to 1888, Wyatt confronts Jessica, who explains that Carolyn and Emma saved her brother Kevin from leukemia using an advanced stem cell treatment. They then proceeded to indoctrinate her into Rittenhouse, raising her from childhood and becoming her "family". When asked by Wyatt if she is actually pregnant, she confirms she genuinely is pregnant and that he is the father. Despite his pleas, she refuses to leave Rittenhouse as she must protect her "family" as well as her baby. During a subsequent shootout in a saloon, Flynn wounds Jessica in the arm, but she manages to escape with Emma.