Horros Oneshot in 2 days and almost no plans as of now

My party was going to play our main campaign, but due to the Schedule Conflicts, we gonna play an oneshot with some other friends instead. I asked which setting they wanted, and they chose an 21th century Horror session. I need quick ideas, rough concepts I can work around.

My current plan is: Taskforce asked to deal with strange ocurrences in smalltown > Town infested by vampires or mimics > Have to defeat the Boss Vampire ou the mimics' Master.