There are quite a few tropes for characters disappearing from shows. They can be written out completely, disappear with no explanation, get killed offscreen or even come back just to get killed. This trope however is when a character stops appearing on the show but is still around in the show's universe. The other characters will see them all the time and reference them, even sometimes being on the phone to them. But this will all happen offscreen. This is most common in soap operas and long running shows. An actor asks for time off and rather than coming up with a way of writing them out, the writers just have the other characters reference them occasionally to let the audience know they're still around. Of course the character can come back eventually though it can go either way. Compare Remember the New Guy, The Ghost Remember that the character has to be mentioned regularly, implying s/he's still around in the other character's lives.
- In Miss Congeniality 2 Gracie has one phone conversation with previous movie love interest Eric Matthews (where we don't see him) ending their relationship and that's it.
- In Scream 2 Sidney's father is back in Woodsboro away from the plot but makes one brief cameo in the third film.
- Charlie Weasley was originally a Ghost until the fourth Harry Potter book but then he goes back to Romania and the family gets letters and presents from him until he makes an appearance in the seventh book. Percy gets similar treatment though he makes at least one appearance in every book.
- In Party of Five Julia's BFF from the first season Nina makes one appearance in season 2 and is mentioned plenty of times after that until season 3 ends where we can assume she and Julia lost contact after school.
- All the characters from that show became this in the spin-off Time Of Your Life which had Sarah Reeves in New York, though Bailey made a couple of appearances.
- Happens a few times in Coronation Street with Sunita being the most notable recent example. She got divorced from Dev and moved into a house outside the street where Dev visited her and their children offscreen regularly. When she returned to the soap, we simply saw Dev arrive at the house and speak to her with no fanfare.
- Similarly Tracy Barlow was sent to prison and made a few appearances inside before Kate Ford left the soap. Deirdre was shown speaking to her on the phone a couple of times and her return was simply her speaking to the prison warden.
- Blanche Hunt's actress Maggie Jones passed away while there was still unaired footage of her and after that ran out Deirdre mentioned she was in Portugal and had a couple of phone conversations with her. Once they had gotten the big storylines finished with, they killed Blanche off officially on the show.
- Most Buffyverse characters got this on the spin-off Angel but Giles was the most prominent example as he never made an appearance on the show but Angel frequently spoke to him on the phone.
- CSI Grissom counts. Sara references him now and then, naturally, since she's his wife, and Nick brought him up once too. And he once appeared onscreen as Sara Skyped with him. His mom was there too.
- Kathy Santoni from Full House She makes a few appearances early on as DJ's pretty and popular friend. She's never seen again after that but is constantly referred to.
- After season 3 in Raw when Dylan and JoJo break up, she has a phone conversation with him in the first episode of season 4 and is frequently referred to as still staying in the city.
- In Cheers after actor Nicholas Colasanto died Coach was said to be out of town on various adventures for the rest of the season. The next season they brought in Woody Harrelson as Woody, Coach's Pen Pal. Sam explains to Woody that Coach had died a few months previously.
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