The Spider Event is an in-room Sanity threat in Keep the Door Locked (Anomaly), the Roblox horror game where you defend a single hotel room against visitors and anomalies. Spiders crawl along your ceiling and burst apart, and standing under one when it pops costs you a large chunk of Sanity. It can appear on any night after Night 2, and there are only two reliable ways to end it.
Quick answer: Let the two hazmat-suited visitors in when they knock. They drop gas bags by the bed that make the spiders explode, and while that happens you just avoid standing directly beneath any spider. If you skip the hazmat visitors, wait roughly 10 seconds for each spider to detonate on its own before you move around or sleep.
How the Spider Event starts and what it does
The event only becomes possible once you are past Night 2, and it can trigger on any night after that. Two signs tell you it is about to begin. First, two people in hazmat suits knock and ask to be let in. Second, cobwebs start forming in the corners of your room, which marks where the spiders will begin crawling across the ceiling.

The spiders never chase or grab your character. They stay on the ceiling and only explode when a player is standing directly underneath them. They also go off on their own after a short time, or sooner if the hazmat operatives gas them. If you happen to be beneath a spider when it bursts, you take heavy Sanity loss. Only a few spiders appear during the event, so the space is manageable if you keep track of where they are.
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Add to Google Preferences →The safest method: let the hazmat visitors in
Admitting the two hazmat-suited individuals is the cleanest way to clear the event. Unlike most knocks in the game, these visitors are not a trap during the Spider Event, and letting them in speeds everything up.

The alternative: wait the spiders out
You do not have to rely on the hazmat operatives. If you ignore them or handle the event on your own, the spiders still explode by themselves. Each one takes close to 10 seconds after it appears and starts crawling before it bursts.
During that window, keep moving so you are never standing under a spider when it pops. Wait until all of them have detonated before you settle down or head to bed. This method costs more time and attention, but it works without opening the door at all.
What to expect by mode and common questions
How often the event shows up depends on which mode you are playing.
| Detail | Behavior |
|---|---|
| Earliest it can trigger | Any night after Night 2 |
| Story mode frequency | Occurs on a single night |
| Endless mode frequency | Can occur multiple times |
| Natural explosion timing | Around 10 seconds per spider |
| Baseball Bat | Cannot be used to kill the spiders |
| Run-ending risk | Yes, if Sanity drops to 0 |
The Spider Event can end a run. If exploding spiders push your Sanity meter to zero, you hit a game over screen. The Baseball Bat is no help here, since you cannot swat the spiders away during the event.
You will know the event is fully resolved when every spider has burst and the ceiling is empty, with no cobwebs marking new arrivals. At that point your Sanity stops being at risk from this threat, and you are free to answer other knocks or sleep to advance the night.






