Like that smell from the bins or that urge to look at your ex's holiday photos, zombies always come back.
Case in point: they've returned to plague the world of Call of Duty: Black Ops 3 in the latest slice of DLC, Eclipse.
We've employed the zombie-stomping skills of YouTuber MrRoflWaffles to give us the lowdown on the new content - with a video of what you can get stuck into and some tips on how to survive the latest onslaught from the undead.
"Zetsubou No Shima brings Treyarch's classic zombies experience to a treacherous island in the South Pacific. Thanks to the research of Division 9, the island is now host to a slew of newly-formed atrocities, all of which are intent on ensuring your demise. Here are some tips to keep you on your feet, no matter what mother nature might throw at you..."
"The Thrasher is Zetsubou No Shima's new boss zombie. First spawning in around the 8th round, they can be quite problematic if you let them charge at you unchecked. Each Thrasher has three glowing bulges of orange swamp gas in various places on its body, which you need to focus your fire on. Keep your distance, and don't let it consume you; you'll have it down in no time."
"Every four to five rounds, an unsettling fog will roll in, and with it will come these beasts: spiders. At close range, they'll leap towards you, spindly spider legs flailing. If too far away, they won't hesitate to shoot a ball of acidic webbing in your direction. Thankfully, their damage output is fairly low - your main worry should be their webbing-up of all the doors you might have opened, isolating you from the rest of your team."
"The Thrashers aren't the only ones with gas problems. Littered around the map are small bulbous pockets of orange gas, which will explode when a player passes by, releasing a cloud fumes into the air. Try to avoid running through the contaminated air wherever possible, as they'll send your character into a coughing fit which is only going to make your life harder."