Story time!
On April Fools day several years ago when I was a college RA (Resident Advisor), my co-RA buddy and I decided to prank some annoying residents in my hall. These three freshmen girls were the prototypical rich, bratty, obnoxious party girls who had no regard for others in the hall. I hated their attitude and lack of respect for others, so we wanted to get back at them somehow. After getting the proper equipment from a nearby hospital I volunteered at, we donned an isolation gown and mask and showed up at their door with the most serious look on our faces. We told them we were sent by the CDC to investigate a biohazardous leak from their air vents. These girls knew I was an RA that never really joked around, and combined with the professional sounding words to them like "CDC" and "biohazardous" (yes they were pretty dumb girls), they listened intently. We walked into their room and told them that the CDC had ordered the residents to be quarantined in the room indefinitely until they could isolate the bug. They were not allowed to leave the room for fear of spreading the disease to others, and the CDC was willing to sacrifice them for the sake of the rest of the population. I told them we were sent as their RAs to provide living material for them so they could spend the rest of their lives in this room. They couldn't believe their ears. We gave them disposable hospital pads and told them they would have to urinate or defecate into these pads, crumple them up and pile them on the side because they were not allowed to leave to go to the bathroom. Their jaws dropped. We also gave them food rations from our emergency RA kits with instructions to split up the calories daily so they wouldn't run out of energy. In addition, we also gave them first aid kits, telling them that the infectious organism in question was known to cause bleeding out of different body orifices and so to use bandages if that ever started to happen. By this point the girls were completely terrified, but we weren't done. We brought a radio along with us on which another RA friend of mine pretended to be a CDC officer relaying all this official-sounding technical talk that he had prepared, e.g. "Alpha and Charlie One, you are 3 minutes from lethal exposure time, we recommend you exfiltrate from the premises soon. Do not let the packages leave the room", etc... (like I said, these girls were really stupid and they were terrified by this kind of talk). By the end of the entire ordeal, two of the girls looked like their entire lives were crushed. And the other girl started crying and wanted to call her mom. At this point we started feeling a little bad, so we decided to end it all. We took off our masks and yelled out "April Fools!". They were completely dumbstruck, and then they just lost it. They started screaming and punching us and telling us how cruel we were, but in the end they were happier when they fully realized they were safe. We got them good.