Introducing a new character who is then inexplicably ignored for a few episodes. Often the result of a clumsy Debut Queue setup.
Alternatively, a common use of Lampshade Hanging to explain why a cast member useful to the plot isn't around. This can be to exclude a character who would make a plot end too early or because the writers want to focus on specific characters.
Poorly used, this will introduce a character who is used for a single arc and then forgotten for long periods of time. The kind of writer prone to this is also liable to keep doing it.
The trope is named after the "Green Room," a backstage area in a theatre where actors who are not required on stage can wait and preparenote , the idea being that the ignored characters are just hanging out there. Not to be confused with shows shot in a green room, and absolutely not to be confused with the film Green Room.
See also Offstage Waiting Room.
- A skillful usage of this technique is in Love Hina, where Motoko (along with her "groupies") is introduced in the first minutes of the first episode, but she immediately leaves on a training excursion, thus freeing up screen time for introductions of the other characters before she gets her turn to take center stage in the third episode. Shinobu is also seen in the first episode, but not really introduced until the second.
- In Kämpfer, Mikoto is seen in the first few episodes via postcards to her childhood friend Natsuru. She's seen again at the end of episode 5, but Mikoto doesn't see Natsuru till episode 6. She remains part of the cast after she returns home.
- In season 3 of the anime adaptation for The World God Only Knows, Kanon, or rather her goddess Apollo, is taken out of commission right away in the first episode, and ends up causing Keima to undertake the conquest of the goddesses after witnessing Lune stabbing her. She doesn't appear again until around episode 8, and even then just as a brief cameo to let Keima know she's still doing okay for the most part. This conveniently allows other girls and goddesses to have more screentime with him, some whom he conquered in earlier seasons, and some who only appeared in brief scenes due to the anime skipping many chapters in the manga between season 2 and 3.
- In Anpanman, thanks to the large amount of characters in the series, a character can end up getting their own spotlight episode and then disappear from the series. Many characters from the early years of the show has had this happen to them, and the movie- and theatrical short-introduced characters end up having the same fate, the newer ones never being transferred into the show.
- In episode 4 of Unlimited Fafnir, Honoka is introduced as a New Transfer Student in episode 4 alongside Tear. But she is quickly forgotten as the latter takes prominence in that episode. She does however interact with Yuu in the next episode after he sees her in the nurse's office.
- In the anime of New Game!, programmer Umiko Ahagon and director Shikuzu Hazuki are introduced in the first episode, way ahead of their manga debuts. Then then proceed to disappear and do nothing till the anime reaches their respective introductions.
- The Power of Five starts off with Matt, who then vanishes after book 2, gets a brief mention in book 3, and then is gone for the first half of book 4.
- The Dresden Files has Bianca's Party in book 3. Everyone and everything introduced the party has a role in the series, according to Word of God. Only Ferrovax has not yet made another appearance.
- In Doctor Who, Robot Buddy K9 is introduced in "The Invisible Enemy", then promptly breaks down for the duration of "The Image of the Fendahl", the script of which was written before K9 was added to the cast.
- Also, Robot Buddy Kamelion is introduced in "The King's Demons" and then disappears for almost an entire season, reappearing only in order to be written out. This was because the complicated and expensive Kamelion prop actually did break down, and the only person who knew how it worked had died. note
- Happened quite a bit in Code Name: Eternity due to the episodes being aired out of order. The two main characters meet a sidekick early in the season, followed by a replacement sidekick in what should have been about halfway through the season; but instead, the sidekicks seem to appear and disappear at random.
- This, mixed with Out of Order happened on M*A*S*H after Charles Winchester's introduction in the season six premiere. A handful of episodes were filmed before a replacement for Frank was found. Winchester's two-part introduction was filmed later, but aired as the premiere.
- RWBY: Adam is introduced in the Black trailer but doesn't appear again until the end of Volume 2, despite the heavy use of White Fang faunus. Similarly, Junior and the Malachite twins are introduced in the Yellow trailer but don't appear until Volume 2, despite their club being associated with Roman Torchwick from the outset.
- G.I. Joe: A Real American Hero had a habit of doing this, with its ridiculously large number of characters and all.
- Transformers suffered from the same thing, some characters only appeared for one episode!
- My Little Pony: Friendship Is Magic has several examples, considering it has Loads and Loads of Characters. Most prominently:
- Princess Luna makes her first non-Nightmare Moon appearance at the end of the pilot two-parter, is reunited with her sister, Princess Celestia, has a party in Ponyville in her honor... and is never mentioned again until Season 2. But then, when she came back, she came back with a bang.
- The zebra Zecora has an entire episode dedicated to introducing her, then she reappears for one quick scene the next episode... and then doesn't reappear until the same episode Princess Luna returns in. Season 2 as a whole has given her considerably more screen time, at least.
- In the first episode Justice League Unlimited, much is made of the League's interest in recruiting Green Arrow and how important he is, only to have him not show up again for thirteen episodes.
- Regular Show: Thomas was shunned to the green room having only appeared with a speaking role in the three episodes that introduce him at the start of season four. He made his re-appearance late on in season four though, twenty-four episodes later.
- Goo was introduced halfway into the third season of Foster's Home for Imaginary Friends, but doesn't appear again until the fourth season, but then is almost a main cast member.
- Mixels, being filled with tons of new characters every series, will often shift focus onto the new characters for a long while, ignoring the previously-created ones, and then the cycle continues when a new series is added.