Sledgehammer Games will be responsible for this year’s new entry to the “Call of Duty” franchise. In its cryptic New Year’s message, the developer may have teased that the upcoming first-person shooter could be set in the 20th century.

Sledgehammer Games shared a video on its Twitter page on Jan. 1 showing an old fashioned mechanical clock ticking from 2016 to 2017. Although the video doesn’t show much more than that, fans can also hear the gong of a bell. This has led to speculations that the bell might be from Big Ben, the Elizabeth Tower of the Palace of Westminster in London, England, according to WWG.

Going back to last December, Sledgehammer Games boss Michael Condrey also shared on his Twitter page a holiday greeting to fans. The tweet included a photo of a M1911 handgun with the “Call of Duty” logo slapped across the the side of the barrel.

To the uninitiated, the M1911 handgun was the standard-issue sidearm of the United States Armed Forces between 1911 and 1986. The pistol was first used in the Philippine-American War and was immensely used during the first and second World Wars.

The M1911 pistol was also used during the Korean and Vietnam wars. The most popular rumor from last year was that Sledgehammer’s new “Call of Duty” game for 2017 will be set during the Vietnam War, as pointed out by PC Gamer.

“Call of Duty: Infinite Warfare,” which was developed by Infinity Ward and released by Activision in November 2016, is set in the far future. Players got to experience interplanetary travel and battling in space.

The game was a top-seller in the United Kingdom, but it failed to meet expectations in the United States with overall fan reception being lukewarm. “Infinite Warfare” also failed to outperform 2015’s “Black Ops III” and it didn’t receive any nominations in the 2016 Game Awards.

EA’s “Battlefield 1, ” developed by DICE, is set during World War I and has received much praise from critics and players alike. It also topped sales for the two months. It’s possible that Activision wants to replicate that same success by winding the clock back instead of forward for its next “Call of Duty” game.