Sometimes people disappear for a few days. That's weird, especially if nobody knows where they are, but not inherently problematic. They may be sick, busy, or out of town. No big deal... Until the other characters try to contact them. They'll text, they'll call, they'll email...but no matter what they try, they won't get a response.
That's when things get serious.
A character who won't respond to any of their messages, no matter who is attempting to contact them, could very easily be in big trouble. In most examples of this trope, they will be in trouble, and this sudden refusal to answer their calls will be the warning sign. Even if they've already disappeared before this, their vanishing act will only start to seem scary when their loved ones can't get in touch with them.
Depending on the context, the unresponsive character may be in a variety of problems. They may be kidnapped, lost with no signal, Cutting the Electronic Leash, or even just in such a bad emotional state they don't want to answer their phone or check their email, and these are just a few of the possible scenarios that can play out. Whatever the problem, though, the others won't start to worry until their texts don't get a response. In some cases, this is because the person is typically such a "phoneaholic" that them not answering their texts is a case of OOC Is Serious Business, but other times, it's just a knee-jerk reaction.
Of course, the problem will rarely be resolved with the person just answering their email. This is usually just the first step to uncovering a bigger issue, and nothing will be fixed until after they find and/or help their friend. The lack of contact is the symptom, not the problem itself. That said, in comedic examples, this may end up being just a paranoid reaction based on limited evidence, with the character's suspicions being proven wrong.
Sometimes overlaps with Impeded Communication, where the messages don't go through specifically because the phone or computer has been compromised; or with Poor Communication Kills, where they are ignoring their messages intentionally.
Finally, don't confuse this with Calling Out for Not Calling, which is when someone gets in trouble because they didn't answer their phone. However that trope exists because people are worried about this trope occuring. While they may overlap in cases of Anger Born of Worry, this trope is about the lack of response being seen as a cause for concern, not anger.
- A downplayed example occurs in Laid-Back Camp when Nadeshiko goes on her first solo camping trip. When Nadeshiko stops answering her text messages, Rin cannot stop worrying about her, and goes out of her way to check on her friend...only to discover that Nadeshiko's older sister Sakura had the same idea. While Rin and Sakura's fears aren't completely unfounded — Nadeshiko can be very foolish on occasion— she is never in danger and her lack of communication really is due to the poor reception in the mountains.
- In My Hero Academia, Tenya Iida usually responds to messages within a few minutes of receiving them. So when Midoriya's text message is read but left without response, it hints to his brooding over the crippling of his older brother and soon going off on his own for Revenge.
- Midsommar: When Dani's replying email to her clinically depressed sister, who had emailed Dani what was basically a suicide note, goes unanswered in the beginning of the film, Dani begins frantically calling her parents and her sister, but her calls keep going to voicemail. Unfortunately, she has good reason to be worried, as her sister killed herself and their parents in a murder-suicide, and it's implied Dani's sister was drugged and manipulated into doing this by the very same cult that Dani herself later gets indoctrinated into by the end of the film.
- In A New Hope, an Imperial officer on the Death Star is suspicious when Stormtrooper TK-421 isn't at his post and doesn't respond to the officer's radio query.
- Jumanji: The Next Level: When Spencer doesn't answer his phone, Martha, Bethany and Fridge go looking for him. When they find his phone in the basement, it has more than a dozen missed calls and more than 40 unread texts on it: mostly from them. This convinces them that he has not just gone to the store or anything mundane, but almost certainly gone back into the game.
- In Brooklyn Nine-Nine, Amy and Rosa realize Jake's been kidnapped because he hasn't sent them any annoying calls or messages for several hours.
- In Chernobyl, after detecting heightened levels of radiation and trying to call everyone around who might be responsible, Khomyuk ends up calling the titular power plant and finding the phone lines are cut off and she is getting no response, making her realize that something is very much going wrong there.
- Daredevil (2015): Throughout the entire series, Matt Murdock would leave his phone at work when he was out doing his vigilante work, making his friends very worried. Some occasions that deserve particular notice are:
- The first is in season 1, when Fisk bombed Hell's Kitchen. It was late at night, their client Elena Cardenas and Foggy both ended up in the hospital, and Matt was not answering his phone, which his friends took as him being potentially lost and injured. Made worse by the fact that Matt's blind and his friends didn't know about his Super Senses at that point.
- Later in Season 1, Foggy, knowing Matt wouldn't pick his phone, sought after him in his apartment, and found him half-dead on the floor.
- In season 2, when Matt didn't pick his phone in the middle of the day, Foggy found him on the rooftops unconscious after being shot at the head by the Punisher.
- In Heroes, it happens twice that Matt tries to phone Mohinder and it goes to voicemail. The first time, Mohinder has mutated himself and gone to work for the baddies. The second time, he's dead in one timeline, locked up in a mental hospital in another.
- House of Anubis:
- Patricia is already a bit suspicious about Joy's disappearance when she first discovers she's gone, but her paranoia doesn't really set in until Joy won't answer her texts, a strange situation because she and Joy are best friends.
- Inverted later on in Season 1; when Patricia gets kidnapped, her friends become concerned because she hadn't called them yet, which she'd have done if she wasn't in trouble.
- When Jerome gets kidnapped by Rufus, nobody has any concerns until he won't respond to any of Mara or Poppy's attempts to contact him.
- Nina's disappearance from the House was already considered worrying, but the fact that she'd responded to none of her friends' messages over the summer were what really made her friends scared.
- Played for Laughs and downplayed in season 3. When Amber fails to respond to any of Willow's friend requests, Willow immediately jumps to the conclusion that Amber might be dead. Patricia resolves the issue in seconds, by picking up the phone and actually calling Amber to confirm she's still alive.
- Inverted in a Dateline episode about the murder of a teenage girl. The cops become suspicious of her boyfriend when they notice that out of the group of friends she was supposed to meet after school, he's the only one who didn't text her to find out where she was, indicating that he already knew she was dead.
- PAYDAY 2:
- Killing/subduing a guard results in someone calling their pager to check up on them. If the pager isn't answered in time, the police will be called.
- The GO Bank and Big Bank heists have phones that need to be answered after the time locks are triggered in stealthnote , with Bain impersonating a member of the staff to try to avoid arousing suspicion. Missing a call results in the police being called.
- Undertale: Papyrus is such an enthusiastic Keet that, if the player kills him, his friend Undyne infers that he's dead because he didn't answer his cell phone after the second ring.
- In Daughter for Dessert, this is the first sign that somethings amiss with Amanda. She disappears, and when the protagonist tries to contact her, she doesnt respond.
- In 2010, Simon Pegg used Twitter to play a prank on his followers, first tweeting that he was going to check weird noises in his attic, then suddenly stopping his online activity for days. Pegg then contacted his sister and his friend Nick Frost so they'd say they had not heard of Pegg in days so they're going to check him - then, following Pegg's instructions, they also stopped their Twitter activity. Next, Pegg used a text in Greek to suggest that a ghost had taken all of them. Lastly, Pegg returned to Twitter pretending that he had been only five minutes in the cellar, and was unaware of all the ruckus. This was all reported on an interview with Conan on TBS here: https://www.youtube.com/watch?v=yAiqBTlks8I
- Echo Rose: Echo and Zip become very concerned when Carma stops answering her phone, and even try and get some presents for her, in case she's just too upset to talk for some reason. Then they discover that her mother doesn't actually know where she's gone, either...
- This can happen when someone has a contact at some other business they have occasionally followed up with for over a year, then suddenly emails to the contact start bouncing and their phone number has been disconnected. Searching their social media sees a sudden cessation of posts in the past month or so. It can take some work to find if they left their job (and are taking a break from the world before or while hunting for another), retired, or died.
- In 1969, Reyna Marroquin's mother became concerned when she stopped writing. Not until 30 years later were her worst fears confirmed—her daughter had been murdered.