Valve is to release new DLC for the first Left 4 Dead game - to complement the release of The Passing DLC for Left 4 Dead 2.
And that's not all - CVG can reveal that the studio is also planning to launch a Left4Dead comic book that "bridges the gap" between the two DLC packs.
Details about the DLC are still thin on the ground ahead of Microsoft's X10 show in San Francisco in a couple of hours.
However, Valve has already announced that The Passing's story involves a meeting between the survivors of Left 4 Dead and Left 4 Dead 2 - and CVG understands that the LFD1 DLC will explain this further.
"We've got DLC coming for Left 4 Dead 1, following [The Passing DLC] that tells you how the Left 4 Dead 1 surviors got there," Valve's Chet Faliszek told CVG.
"The whole of Left 4 Dead leaves you in a little bit of a mystery as to some of what happens - not least when you kind of see a little bit of the tail-end of the Left 4 Dead 1 story, as you get on your way to [L4D2 campaign] Dark Carnival.
"With that, we actually have a comic book coming out between the two DLCs, which will help us give a little bit more of a back story to explain what's happening in the world."
When asked why Valve decided to make the odd turn to release DLC for an older game, Fasliszek added:
"We've always thought of it as the Left 4 Dead world, and having new characters and expanding that world and point of view. I'm a big fan of the idea that once fiction is created, gamers have it in their head and it's real.
"I go back to when David Bowie created characters like Major Tom - he made [Major Tom's] world feel like it was real, and each song gave another version of it.
"To me, that was really cool. We wanted to do that in Left 4 Dead: There are all these things going on in this world and its stories that feel real to players, so let's have them interact with one another."