What began in 2008 as an unannounced bonus mode tucked behind the campaign of Call of Duty: World at War became one of gaming's most enduring cult phenomena. Over more than fifteen years, Treyarch's Zombies mode grew from a four-wall survival experiment into a sprawling mythology of mad science, interdimensional horror, celebrity-stacked casts, and hidden songs. This page traces the real people, studios, and stories behind Nazi Zombies.
Origins: A Side Project That Became a Pillar
Zombies was never part of the official plan for Call of Duty: World at War (2008). During a difficult development cycle, a small group at Treyarch began experimenting with a cooperative survival mode pitting players against endless waves of the undead, reusing assets already built for the main World War II campaign. There was no dedicated budget and no marketing; it grew out of an internal idea that the team simply found fun to play.
The result was Nacht der Untoten (German for 'Night of the Undead'), a single derelict bunker where up to four players boarded windows, bought weapons off the walls, and survived as long as they could. It shipped as a hidden mode, originally unlocked only after finishing the campaign, with no fanfare. In this first version the four survivors were unnamed U.S. Marines, not the iconic named crew.
Word of mouth did the rest. The mode's popularity caught Treyarch off guard and turned an unbudgeted experiment into a franchise cornerstone. Zombies expanded across the World at War map packs and has appeared in nearly every Treyarch-led Call of Duty since, eventually becoming a marquee selling point alongside campaign and multiplayer.
The Original Crew and Their Voices (Ultimis / Primis)
The famous four-person crew did not debut in Nacht der Untoten. The named characters, retroactively called 'Ultimis,' first appeared in Shi No Numa, the third World at War Zombies map: American Marine 'Tank' Dempsey, Soviet soldier Nikolai Belinski, Japanese Imperial officer Takeo Masaki, and the German scientist Dr. Edward Richtofen. A second, younger 'Primis' version of the same four was later introduced in Black Ops III, voiced by the same core actors. Anchoring the storyline are Dr. Ludwig Maxis and his daughter Samantha Maxis, whose fate at Group 935's Der Riese facility drives much of the early lore.
Several of these performers have voiced their roles for well over a decade, which is part of why the cast feels so iconic to longtime fans. Tom Kane, the original voice of Takeo, later stepped back from voice work after suffering a stroke, and the role has since been recast (Nelson Lee voices Takeo in the newest Black Ops 7 crew).
The Celebrity Guest Casts
Treyarch repeatedly raised the mode's profile by casting recognizable actors, often drawn from horror and crime cinema, to play the survivors on special maps.
Call of the Dead (Black Ops, 'Escalation' DLC, 2011) was set on a frozen film location and featured a horror-movie all-star cast, with legendary director George A. Romero appearing as himself as the map's boss. Mob of the Dead (Black Ops II, 'Uprising' DLC, 2013) cast a quartet of crime-film actors as 1930s Alcatraz gangsters. Dead of the Night (Black Ops 4, 2018) assembled a roster of acclaimed British and American actors as guests at a haunted English manor in 1912.
The Music: Hidden Songs and the Teddy-Bear Tradition
Music is central to the Zombies identity, and most of it comes from Treyarch composer and sound designer Kevin Sherwood, who wrote and produced the mode's signature easter-egg songs. His longtime collaborator, singer Elena Siegman, provided vocals on many of the most beloved tracks, including 'Lullaby of a Dead Man,' 'The One,' 'Beauty of Annihilation,' '115,' 'Abracadavre,' and others across World at War, Black Ops, and Black Ops II/III. Siegman also performed many of the Perk-a-Cola jingles such as Juggernog.
A defining ritual is the hidden song easter egg: on many maps players activate a secret vocal track by finding and interacting with three concealed objects, most famously three teddy bears scattered across the level. Activating all three swaps the ambient audio for a full song, a tradition that began in the early maps and became a fan-hunted staple of nearly every release.
Other vocalists expanded the palette over time. Singer-songwriter Malukah performed tracks such as 'Always Running' and 'Where Are We Going,' and composer Clark Aboud (credited as Clark S. Nova) contributed vocals and music to later songs. Treyarch also licensed outside artists: the band Avenged Sevenfold wrote 'Not Ready to Die' for Call of the Dead and 'Mad Hatter' for the Black Ops 4 map IX, with their existing single 'Nightmare' featured on Moon, while a hidden easter egg on the map 'Five' plays Eminem's 'Won't Back Down' (featuring P!nk).
The Architects: Treyarch's Developers and Writers
Zombies is a Treyarch creation, and a handful of developers shaped its story and design over the years. Jimmy Zielinski, an animator who was part of the original World at War Zombies team, is widely credited as a key creative force behind the early mode and its easter eggs; he served as creative/design director for Zombies through Black Ops and most of Black Ops II before leaving the studio in late 2014.
Jason Blundell became the defining storyteller of the mode's middle era, directing the Zombies narrative through Black Ops II, III, and 4 and rising to co-studio head and game director at Treyarch. His Black Ops III work, in particular, is credited with weaving the sprawling Aether saga into a cohesive epic. Blundell departed Treyarch in early 2020 after roughly thirteen years.
Craig Houston has been the throughline writer. He has written for Treyarch's campaigns since Call of Duty 3 (2006) and served as the principal writer for Zombies starting with World at War in 2008, continuing as lead and later senior lead writer across the franchise's evolution, including the Dark Aether era and Vanguard Zombies. The constant across all of it is the studio itself: Treyarch, which originated the mode and has steered every mainline Zombies experience.
Dead Ops Arcade: The Real Origin (Myth vs. Reality)
A popular fan legend holds that an outside solo developer built Dead Ops Arcade alone, sold it to Call of Duty, and 'made millions.' The documented record does not support that framing. Dead Ops Arcade was created inside Treyarch as an internal passion project, championed by the studio's own Chief Technology Officer, David King.
It debuted in 2010 as a hidden easter egg in the original Black Ops: players could break free of the interrogation chair at the main menu (as Alex Mason), access a CIA terminal, and type 'DOA' to unlock a top-down, twin-stick arcade shooter packed with 1980s arcade nostalgia. King has described it as a homage to the classic arcade games he loved growing up in the '80s, saying the mode 'started out as a simple homage' before 'things just kept getting crazier from there.' Treyarch itself frames it as one of its favorite internal traditions and an 'ultimate internal passion project,' and the mode has returned in sequels (Dead Ops Arcade 2 in Black Ops III, and later entries through Black Ops Cold War and Black Ops 7).
Verdict: the 'solo developer sold it to Call of Duty and made millions' story is a myth. What is real is that one person, Treyarch CTO David King, was the driving visionary behind Dead Ops Arcade, but he was already a senior employee of the studio, it was a collaborative in-house creation rather than a one-man product, and there is no documented outside sale or 'millions' payout. The accurate version is an internal side project that grew into a beloved recurring mode.
The Dark Aether Reboot (Cold War Onward)
With Black Ops Cold War (2020), Treyarch launched a soft reboot of the Zombies storyline known as the Dark Aether saga, set in 1980s and serving as a new continuity distinct from the original Aether story while still tied to it through certain returning characters. The new narrative centers on rival Cold War organizations racing to weaponize an interdimensional realm.
On the Western side is Requiem, a covert CIA research division tasked with containing Dark Aether outbreaks, with field operations connected to returning Black Ops figure Grigori Weaver (voiced by Gene Farber) and featuring an adult Samantha Maxis (Julie Nathanson) as a central character. Opposing them is the Omega Group, a KGB/Spetsnaz-backed outfit led by the returning villain Colonel Lev Kravchenko, seeking to harvest the resource Aetherium for the Soviets. The story unfolds across maps such as Die Maschine, Firebase Z, Mauer der Toten, and Forsaken, and continues into later titles (Black Ops 6 and beyond), with Edward Richtofen reprised by Nolan North in his Dark Aether incarnation.