Telltale used to be a bit inconsistent with their releases, but as of recently they've managed to get things working like clockwork. As such, Episode 4 of the Batman: The Enemy Within adventure game series is set to arrive tomorrow, on January 23rd, which is exactly two months from the previous episode - just as Telltale promised!
There aren't that many details available just yet, for obvious spoiler-related reasons, but what I can tell you is that Episode 4 will focus heavily on the impending showdown between Batman and the Joker. As for the side-stories, expect to find out what's truly motivating Amanda Waller and the Agency, how John Doe will handle the truth about Bruce, as well as when and how the Pact will regroup.
If all of that is a little bit too vague for your tastes, you can find out more in the recently posted trailer down below. Just keep in mind that the videos features a variety of minor spoilers for both Episode 4 and the ones that came before it, so only dive in if you don't care about such things. Here's the video:
You can learn more about Batman: The Enemy Within, as well as all of the episodes, by heading over to the official website. That said, don't expect to find too much as Telltale is thankfully tight-lipped when it comes to the important story details.