If you are not familiar with Sherlock from BBC, then I would highly recommend going on Netflix and binge-watching all 3 Seasons ASAP.  Each of the three seasons has three different episodes that run a movie length time of approximately an hour and a half, and they are well written suspenseful adaptations of Holmes and Watson in a modern-day London setting.   After the odd Victorian look of The Abomindable Bride movie last holiday, Sherlock is about to go back to its roots when it returns for Season 4.  This is what is known about Sherlock Season 4 Release Date and spoilers. 

Master Herald is reporting that Jim Moriarty (Andrew Scott), the "crime consultant" and Holmes most well-known nemesis from the Victorian source material will be making a comeback.  This should come as no surprise being that Season 3 really made a point of showing how he had hacked the screens of London.  Of course, he did supposedly die at the end of Season 2, but then again, so did Holmes. 

There have been a lot of rumors that there will be a third Holmes brother coming to the show, and he will be played by Tom Hiddleston.  Hddleston is most famous for his role as the god of villainy Loki in the Thor movies, and the showrunners wondered if they could get the very busy actor on board.  So far, Hiddleston has openly expressed his love for the show and would not take the role lightly as Sherrinford Holmes. 

Not that the two protagonists, Sherlock (Benedict Cumberbatch) and Watson (Martin Freeman) are any less busy.  Considering that Cumberbatch will be Dr. Strange and Freeman will also be appearing in Captain America: Civil War, it is a wonder that the Sherlock show can still go on. 

One thing that was established on Season 3 was the role of Watson's wife, who turned out to be a moonlighting spy in a bizarre twist and pregnant by the end of the season.  Martin Freeman has hinted that his character's wife Mary will die, and it will happen due to childbirth.  It is odd that he would give such a hint like that, as the show is quite popular and one would think that this actor would be contracted not to leak such spoiler information.  Considering that Holmes has "died", and Moriarty will probably be returning, will Mary make a comeback if she dies? 

However, there are rumors that Season 4 of Sherlock is going to be very accurate to the source material, and showrunner Mark Gatiss has confirmed that Season 4 of Sherlock will not have a happy climax.  Considering the show's darker nature, most viewers should not at all be surprised by that, but eventually, Sherlock has to come to a close. 

As far as the release date for Season 4 is concerned, Sherlock Season 4 should be back on or before January 2017, according to iDigitalTimes.  CNET has recently revealed still photos from the filming of Season 4 that do not reveal too much.