The characters sense that someone close to them is suicidal, and they try their best to prevent it, but not by talking to them about it directly or calling them medical help. Instead, they decide to keep them company and spend time with them to make sure they don't have an opportunity to harm themselves.
There might be several reasons why someone might decide to take this approach instead of immediately calling for emergency help or talking about the issue directly. Maybe they want to spare the suicidal the embarrassment. They might be afraid of their reaction if they talk about the suicide bluntly and straightforwardly, especially if trying to talk directly might inadvertently give them the idea of committing suicide if they hadn't been thinking of it before. They might want to minimize the chances of having them being taken off to a mental hospital (especially if they fear that calling in medical help or the police might be the last straw that pushes the suicidal into going through with it).
In some jurisdictions, suicidal people can be detained in mental hospitals until their urges are either finished, or the patient is undergoing treatment. They might be subjected to an involuntary psychiatric hold, where it's the authorities who are doing the guarding.
Compare Talking Down the Suicidal. May lead to Interrupted Suicide, Bungled Suicide, or Happily Failed Suicide. If the person under watch wasn't suicidal after all, see Mistaken for Suicidal. This trope often goes along with Prelude To Suicide.
If you or someone you know feels suicidal, there are numbers you can call.
- Downplayed in Ano Ko Ni Kiss To Shirayuri Wo, when Kurosawa runs into Shiramine who is obviously in considerable distress after a difficult talk with her overly demanding parents. When Shiramine then declares that she is gonna skip school for the first time in her life to go "to the sea", Kurosawa starts quietly following her at a short distance, despite Shiramine's insistence that she not be followed. It turns out that Shiramine didn't really have any suicidal thoughts — she just was so hurt by her mother's words that she needed to get away for a night, and afterwards, she thanks Kurosawa for not leaving her alone.
- A Hollow in Equestria: Rainbow Dash is put on suicide watch due to the repeated mental trauma she'd been subjected to by Nightmare Moon has left her unable to know what's real anymore.
- Our Eternity Together: Mystic is being watched after attempting to take her own life. Her logic? She believes that if she's dead, the Cursed God will have no reason to go after her friends. It gets to a point where she's itching to escape the sanctuary.
- RWBY: Scars: After Blake yells at Weiss while out on a date, Weiss comes back to the dorm upset and questioning whether everyone would be better off if she was dead or not. Yang and Ruby hug her and try to calm her down. They decide to keep a careful eye on her for the next few days.
- The Fifth Act: After the attempted murder-suicide and finding out the truth about Cloud, the First Class Soldiers place Cloud on a suicide watch. They deliberately keep Cloud's Ribbon away from him so they could put him to Sleep or Paralyze him if Cloud looks to inflict harm.
- To Hell and Back (Arrowverse): After Barry went missing at fourteen during his botched trip to China and was presumed dead, his father Henry (framed for his wife's death and incarcerated in Iron Heights) tried to commit suicide in grief. He was stopped, and the prison put him on suicide watch. Barry's best friend, Iris, went even further and made the effort to visit Henry on a frequent basis to give him a reason to keep living, knowing that Barry wouldn't have wanted his father to die before getting out.
- XCOM: RWBY Within: Coco is on suicide watch by her therapist after a joking quip reveals extremely deep-seated guilt for her inadvertent role in the downfall of Beacon and the deaths of many stadium-goers.
- Community, "Advanced Dungeons & Dragons": Fearing one of the college students is suicidally depressed, the study group decides to intervene by inviting him to play his favourite game Dungeons & Dragons with them.
- Crazy Ex-Girlfriend: In season 3, after Rebecca tries to overdose on anti-depressants, her group of friends stay in her house for a while to give her support and make sure that she is okay.
- An episode of Law & Order has a suspect sent to Rikers (a correctional facility) and put on suicide watch. He still manages to kill himself.
Briscoe: I specifically asked for him to be put on suicide watch. Apparently, here at Rikers, they watch you commit suicide.
- One episode of Monk sees the titular detective being put on formal suicide watch after a case shatters his confidence in his abilities.
- In one episode of Reno 911!, Trudy Wiegel gets put on suicide watch after accidentally asphyxiating herself in her car. With everyone else forced to be nice to her for a change, she milks the situation for everything it's worth.
- The Walking Dead, the B-plot of "18 Miles Out" has Beth become suicidally depressed and try to get a knife to slice her wrist. Lori and Maggie watch her and try to talk her out of it, but Andrea believes Beth should have the right to choose how to live and when it is her turn to watch her she leaves her alone so she can attempt suicide if she wants. Beth manages to cut her wrist but fails to kill herself and immediately regrets it, letting Lori and Maggie help her, and Lori and Maggie call out Andrea for letting Beth make the attempt with Maggie banning her from setting foot in her house ever again.
- The Wire: After Officer Prezbylewski accidentally shoots another police officer while chasing a suspect in the projects, his superior Lt. Daniels comes to visit a despondent Prez as the rest of the department heads are discussing what to do next. After Daniels leaves the room, he tells Deputy Rawls to send somebody home with Prez to make sure he doesn't kill himself out of guilt.
- Around the World in 80 Days: Aouda and Passpartout are both worried that Mr Fogg might end it all after he loses the bet and is financially ruined. Passepartout keeps watching him.
"From the words which Mr Fogg dropped, she saw that he was meditating some serious project. Knowing that Englishmen governed by a fixed idea sometimes resort to the desperate expedient of suicide, Passepartout kept a narrow watch upon his master, though he carefully concealed the appearance of so doing."
- The Belgariad: in the prequels, Belgarath writes that after learning of Poledra's death, he had to be chained to a bed, with his fellow sorcerers taking turns jamming his magic, so he wouldn't commit suicide.
- In novel Death on the Nile with Hercule Poirot, Cordelia is forced to stay with Jacqueline all night after Jacqueline shoots her ex-fiance Simon in the leg. This is a carefully-arranged alibi for the murder.
- John Dies at the End: During the epilogue, John instructs Amy to spend the night at Dave's house, ostensibly because they've all just learned that Dave is a clone from Korrok's world and they need to be sure that he won't become a monster. Later that night, Dave finds that his medicine cabinet has been emptied and a pair of scissors is missing from his bathroom. He remembers that Amy was in there before him, and realises she's actually there to make sure he doesn't kill himself over the afore-mentioned revelation.
- Persuasion: Captain Frederick Wentworth does not leave his friend Captain James Benwick for a week after he's told that his fiancee Fanny Harville died. It's implied Captain Benwick suffers so much that he could do something very desperate.
- In the third book of the Sword of Truth series, a seer tells Kahlan that her half-sister (who suffered a bad case of Prison Rape resulting in Rape Leads to Insanity) is dreaming of hanging herself. She then says she'll sleep next to her this night.
- In the Jem episode "A Change of Heart", Minx decides to become nicer after Rio saves her from drowning. Her bandmates Rapture and Riot don't like this sudden change in personality and kick her out. With nowhere to turn to, Minx flees to Rio and when he rejects her she tries to jump off a building. The rest of the episode revolves around Riot and the Holograms walking on eggshells around Minx as she tries to pay back her imagined debt to Rio.
- King of the Hill: In the episode "Pretty, Pretty Dresses", Bill becomes suicidal as the approaching Christmas season reminds him of his ex-wife Lenore. This prompts Hank and his other friends to take turns watching over him to make sure he doesn't kill himself, including one memorable scene of Dale threatening him at gunpoint.
- Rick and Morty: In "The Whirly Dirly Conspiracy", Rick takes Jerry on an adventure at Morty's request; apparently Morty was worried his father might kill himself over his recent divorce. However, Morty later admits that he only said that because he wanted a break from going on Rick's adventures himself.