Hello Games' Guildford office was flooded during the Christmas holidays after torrential rain stormed the town.
The nearby riverbank broke, leading to what the studio described as a "biblical amount" of water pouring in through the windows.
Tweeting on Christmas Eve, the Joe Danger and No Man's Sky developer said "everything in the office has pretty much been lost". The studio also tweeted that its insurance did not cover the damage as the office was based in a flood risk zone.
Develop has more details.