After Zatanna sends a magically spiked bottle of champagne to Clark and Lois for their bachelor/bachlorette parties, the gang blacks out after the toast, only to wake up the next morning and realize they can't remember anything about the night before. While trying to retrace their steps, Lois realizes she lost her engagement ring and drags Oliver back to the Fortune Casino where she thinks she lost it. The two run into Amos Fortune (guest star JAMES KIDNIE), the eccentric casino owner, who accuses them of stealing money from him. Meanwhile, Clark tells Chloe he has a memory of stealing an armored truck the night before.
Chloe and Oliver are mistaken for FBI agents investigating Desaad's recent string of murders and the pair are kidnapped by Desaad's minions. Desaad (guest star STEVE BYERS) tries to infect Chloe with the darkness. Meanwhile, Lois tells Clark he needs to be more careful with his identity and suggests a disguise.
Clark is surprised to see Martha (former series star ANNETTE O'TOOLE) on the news speaking at a pro-vigilante rally. Meanwhile, Lionel reveals his existence to the world and reclaims LuthorCorp from Tess and Oliver. As Clark deals with a shocking event, Lois and Chloe decide to cheer him up by showing him videos from thousands of vigilante supporters professing their support for The Blur. (Videos were created and submitted by actual "Smallville" fans.)
Chloe Sullivan returns. Clark, Oliver, Lois and Dinah are released by the VRA after being captured at Hawkman's funeral but each of them has flashbacks of Chloe holding them against their will. When Chloe returns, Dinah warns the others that Chloe may now be a traitor. Oliver dismisses her concerns, but Clark is unsure if he can trust Chloe after she disappeared without an explanation.
The VRA is in full effect and things take an unfortunate turn of events after the Green Arrow tries to stop a mugging but is attacked by citizens for being a super hero. Clark discovers that the civilians who attacked Oliver were all marked with a darkness tattoo. Carter Hall and Star Girl (guest star BRITT IRVIN) return to help Clark deal with Slade's (guest star MICHAEL HOGAN) re-emergence after he kidnaps Lois.
Tess acquires a Kryptonian box that once belonged to Lionel Luthor (former series star JOHN GLOVER). When Clark accidentally activates the box, he's transported to a parallel universe where Lionel found Clark in the cornfields instead of the Kents. In this universe, Clark Luthor is a murderer and Lois is engaged to Oliver -- and both of them hate Clark. Clark must be careful not to tip off Lionel that he's not his son while trying to figure out how to get back to Earth where the monster Clark Luthor was transported in his place. Executive producer Kelly Souders makes her directorial debut.
In an effort to protect the rest of the team, Oliver decides to register for the Vigilante Registration Act to see what the government plans to do with the new law. As he suspected, it was a trap to lure superheroes to an undisclosed location where he is confined to a jail and subjected to a battery of brutal tests under the supervision of Col. Slade (guest star MICHAEL HOGAN -- Battlestar Galactica). Aquaman (guest star ALAN RITCHSON) and his new wife Mera (guest star ELENA SATINE) team up with Clark to free Oliver. Lois is frustrated when Clark continues to push aside her offers to help the team and sets out to prove she can play with the big boys. Series star Tom Welling directs.
Lois finds a video made for her by her mother, Ella Lane (guest star TERI HATCHER), before she died. After watching the tape, Lois makes a drastic decision about her relationship with Clark that takes her to the Fortress, where she comes face to face with Jor-El and Lara. Meanwhile, Tess has a nightmare involving herself as a child and a music box. Upon awakening, she finds the music box in Luthor mansion and sets out to find out who planted it there. Clark accompanies her to an orphanage run by Granny Goodness (guest star CHRISTINE WILLES) who may not have the young girls' best intentions in mind. One of the young women living there, Harriet (guest star LINDSAY HARTLEY), finds Clark snooping around and decides to take matters into her own very sharp hands.
Concerned about Lois's safety, Clark diverts her away from covering the Vigilante Registrations Act by suggesting she cover another story. After he comes clean with her, an angry Lois tells him that she can take care of herself -- but when a flat tire strands their car in the middle of nowhere, their plans take a turn for the worse and Lois ends up in serious danger. Meanwhile, Tess searches for a cure for Alexander (guest star CONNOR STANHOPE), who is rapidly aging.
The General (guest star MICHAEL IRONSIDE) and Lucy Lane (guest star PEYTON LIST) decide to drop in on Lois and Clark for a surprise Thanksgiving dinner. Clark and the General get off to a rocky start after Lois's father bashes the superheroes and tells Clark he is trying to pass a vigilante registration law. Meanwhile, in an effort to stop the vigilante registration act from being passed, Rick Flagg (guest star TED WHITTALL) lies to Lucy in order to lure Clark away from the farm long enough for him to assassinate the General.
