It’s 2005 and Infinity Ward has just completed work on its second Call of Duty project, Call of Duty 2.

With Treyarch set to handle the lead development duties on Call of Duty 3, the team at Infinity, exasperated with the World War 2 setting, decide to take its next title in the series in a different direction, vowing never to return to the ‘40s again.

Several concepts are put forward and the studio decides to go with a modern theme, opting to avoid the contention that could potentially arise with choosing to set the game in a contemporary conflict. A story is written, and for the first time in its history, Infinity Ward elect two teams to work on the game: one for the campaign and one for multiplayer.

A month out from launch day, a story level is released as a demo on PC; the developer receives a swathe of negative feedback. Undetered, Infinity Ward releases Call of Duty: Modern Warfare in November 2007. The game attracts plaudits from players and critics alike, and sales exceed 10 million units by June the following year. CoD 4 is the first title in a new Activision strategy that still exists today: releasing a full Call of Duty title every 12 months.