It's early days yet, and there's no firm air date, but it looks like HBO is keen to get True Detective back on the air as soon as possible.
In fact, if rumours are to be believed, they've even begun casting the major roles. According to Tracking Board, the Oscar-winning actor and star of House Of Cards, Moonlight and Luke Cage - Mahershala Ali - has been approached to lead the third season of True Detective.
Ali won his first Oscar in the Best Supporting Actor category for his performance as Juan, and has been pretty much in demand non-stop since he broke through with House Of Cards, playing Frank Underwood's henchman-turned-enemy Remy. Tracking Board's sources point out that it's still early days for the TV show and Ali hasn't yet signed on fully, but they're confident he will.
As for plot and the like, there isn't a screed of information to be found. Showrunner / creator Nic Pizzolatto is currently working on the screenplay for the new season and is being helped along the process by David Milch, who created NYPD Blue, Deadwood, Hill Street Blues and is kind of a legend in TV writing. There's no word yet if even a script or outline has been turned into HBO yet, but they're clearly at an advanced stage with it if they're out casting roles for it already.
So, thoughts on Mahershala Ali? He's a brilliant actor, and you only need to look at any one of his roles - be it something like Netflix's Luke Cage or House Of Cards, or even his supporting roles in Moonlight and The Place Beyond The Pines - to see that he has an incredible range and depth of talent. The past two seasons of True Detective all had heavy hitters lead the show; McConaughey / Harrelson and Vaughn / McAdams / Farrell, so putting a recent Oscar winner like Ali makes sense.