Warning! Major SPOILERS for Legends of Tomorrow season 7 episode 10 ahead!
The Flash’s most successful villains.
Legends of Tomorrow season 7 focused a lot on the group’s inability to travel through time, as the show had the Legends abandon time travel for six episodes before getting access to the first time-travel machine ever built. As their Waverider was destroyed by another identical Waverider at the beginning of season 7, their efforts focused entirely on trying to get back to that Waverider and understand who wanted them dead. When they learned that a group of robots who believed to be the original Legends tracked them by tracking timeline disruptions guided by an evil AI version of Gideon, Sara (Caity Lotz) and the rest of the crew decided to lure them to a fixed point in history, whose disruption would have caused a time aberration that the robot Legends couldn’t have ignored.
Trying to stop the assassination of Archduke Franz Ferdinand of Austria in 1914 in order to disrupt the timeline in an unavoidable way led Sara to meet Eobard Thawne (Matt Letscher) again. Nevertheless, the version Sara met in Legends of Tomorrow season 7 episode 10 wasn’t bent on changing timelines to satisfy his needs, instead, his purpose was to protect that fixed point in history. Although Letscher’s Thawne never returned to the Arrowverse as often as Tom Cavanagh’s version of Reverse-Flash, this particular return proved especially tricky, as Letscher’s Thawne had been vaporized by Black Flash, therefore completely erased by any timeline, in Legends of Tomorrow season 2.
Before being vaporized by Black Flash, Letscher’s Thawne had created the Legion of Doom with Malcolm Merlyn (John Barrowman) and Damien Darhk (Neal McDonough), precisely to fight Black Flash by Black Flash, who then vaporized Thawne.
Legends of Tomorrow season 7 episode 10 ended up not retconning Letscher’s Thawne’s fate, only updating it. According to what Thawne told Sara in the episode, the time wraiths had other plans for him after Black Flash erased him. Thawne didn’t end up in 1914 in a sort of penance for his crimes against the timeline, instead, he truly was a changed man. The Time Wraiths pulled him back from nothingness, and after they stripped him of his powers, they re-educated Thawne and assigned him to protect a specific fixed point in history. Letscher’s Thawne even said that he saw the Time Wraiths’ point, that “history cannot and should not be changed,” in contrast to anything he did in his past, both in The Flash and Legends of Tomorrow. He truly seemed changed, as he was willing to make it seem Archduke Franz Ferdinand’s assassination didn’t succeed, helping the Legends go back to their Waverider in the meantime. Letscher’s Thawne will be back in Legends of Tomorrow season 7 episode 11.
Legends of Tomorrow airs every Wednesday on The CW.