History RememberTheNewGuy / LiveActionTV

* ''Series/AgentsOfSHIELD'' introduces us to Agent Eric Koenig (played by Patton Oswalt) who shortly after his introduction is [[spoiler:murdered by Ward]]. But! He has a twin brother, Billy, also a S.H.I.E.L.D. agent, who is introduced in the last few minutes of the season a few episode later. By the time the second season comes around we see there's a ''third'' Koenig brother as well, Sam. We never get an explanation for how either Koenig ended up working with Coulson's team.

* ''Series/Batman1966'': In season 3, Calamity Jan is established as Shame's long-term girlfriend even though, in his previous appearance, he had a different female accomplice and implied lover, who is never mentioned in season 3.

* ''Series/LukeCage2016'': Season 2 introduces us to Mariah Dillard's estranged daughter Matilda Maybelline "Tilda" Johnson, who was never seen or mentioned in season 1. It's explained in this case that Tilda was given up for adoption by Mama Mabel when she was young, and Mariah didn't like being around her as she was conceived as a result of [[ChildByRape Mariah being regularly raped by her uncle Pete]].

* Helen's sister Casey was added to the cast in season 6 of ''Series/{{Wings}}'' despite having never been mentioned before. Helen had mentioned a sister in a previous episode, but that sister was named Lorraine and was clearly a different person from Casey (who is implied to be her only sister), making this a {{Retcon}} as well.

** The titular villain of the ''Series/{{Torchwood}}'' episode [[Recap/TorchwoodS2E5Adam "Adam"]] has this as his ''[[BackstoryInvader main power]]''. He can also change their personalities, and turns Torchwood into a self-insert fanfic: Jack becomes his new best friend, Toshiko becomes his girlfriend, and Owen becomes an office dork with a crush on Tosh. Unfortunately for him, it backfires when he feeds himself into Gwen's memories: As a side effect, Gwen forgets ever having met her live-in fiancé Rhys and subsequently thinks he's a crazy stalker who's put up fake photos of them together.

** The titular villain of the ''Series/Torchwood'' episode [[Recap/TorchwoodS2E5Adam "Adam"]] has this as his ''[[BackstoryInvader main power]]''. He can also change their personalities, and turns Torchwood into a self-insert fanfic: Jack becomes his new best friend, Toshiko becomes his girlfriend, and Owen becomes an office dork with a crush on Tosh. Unfortunately for him, it backfires when he feeds himself into Gwen's memories: As a side effect, Gwen forgets ever having met her live-in fiancé Rhys and subsequently thinks he's a crazy stalker who's put up fake photos of them together.

** The titular villain of the ''Series/Torchwood'' episode [[Recap/TorchwoodS2E5Adam "Adam"]] has this as his ''main power''. He can also change their personalities, and turns Torchwood into a self-insert fanfic: Jack becomes his new best friend, Toshiko becomes his girlfriend, and Owen becomes an office dork with a crush on Tosh. Unfortunately for him, it backfires when he feeds himself into Gwen's memories: As a side effect, Gwen forgets ever having met her live-in fiancé Rhys and subsequently thinks he's a crazy stalker who's put up fake photos of them together.

** According to the book, Ned Stark was executed in front of the Great Sept of Baelor. The series had no budget to show off the sept in the first season so it is jarring to say the least when this grand building suddenly appeared in later seasons.

* ''Series/PersonOfInterest''':

* Nothing is known about ''Series/PersonOfInterest'''s Detective Petersen other than that he works for HR and enjoys shooting people. Miller, the other underling introduced in the same episode, is treated as a random mook, yet Petersen seems to go some way back with Simmons and is recognizable to Fusco. However, he's completely new to the viewer.

* ''Series/TheWalkingDead'': It's become common since a bit after they settled in Alexandria for the main group to be on a first name basis and implied to be connected strongly with characters who were never mentioned before. Many are {{redshirt}}s, though some become more important.

** The most common reaction to the image of Lord Axell Florent being burned alive is to wonder who the hell he is.

*** The ''same story'' introduces Captain Mike Yates, the Brigadier's right-hans man, who's just suddenly there as part of the UNIT set-up with no real introduction. The Doctor even says Yates was already with UNIT during the Nestene invasion in [[Recap/DoctorWhoS7E1SpearheadFromSpace "Spearhead from Space"]] the previous season, even though we never saw him.

* ''Series/{{Justified}}''" Despite his role as Ava's last known relative and protector, Zachariah Randolph is never seen or mentioned before the final season, despite the number of situations Ava's been in where she might have used him as a confidant or protector (the aftermath of Bowman's death, her time in prison, etc.).

* ''Series/Frasier2023'' introduces Alan Cornwall, an old college buddy of Frasier's, who never appeared nor was mentioned on either the original ''Frasier'' or ''Cheers'', despite this series returning Frasier to Boston, where the latter was set.