Warning: The following synopsis reveals critical information about the third episode of season three.

The CW has released the official summary for "The End of the Affair," which airs on September 29 and introduces us to Stefan's ex-girlfriend, played by Claire Holt. It will also deliver what is sure to be another exciting, classic Vampire Diaries flashback.

Read the description below, if you so choose.

Klaus and Stefan arrive in Chicago, where Stefan is reunited with a vampire who hasn’t really moved on from her interest in him decades earlier. In a flashback to Chicago in the 1920s, Stefan comes face-to-face with a shocking chapter from his wild past. After Damon gets a tip on Stefan and Klaus’ whereabouts from an unexpected source, he and Elena follow their trail. Back in Mystic Falls, Tyler is concerned about Caroline and turns to Sheriff Forbes for help.

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