Mark Gattis, co-writer of BBC crime drama "Sherlock" has confirmed that Season 4 of the hit detective drama is unlikely to premiere anytime before 2016 - news that will leave fans hugely disappointed.

While replying to questions in Brazil, Gattis explained that the delay is owing to the fact that it takes time to write three 90-minute episodes of the show and also to assemble everyone together at the same time - with all their varying commitments and schedules - to commence production.

British tabloid The Mirror quoted Gattis as saying, "Writing three films is quite a lot of work and then getting everyone together... (it's) increasingly difficult to get everyone's diaries to align, so we couldn't really do more than three every couple of years I'm afraid."

Although the "Sherlock" production team would be happy to reduce the two-year waiting period and bring Season 4 to fans sooner, they has indicated that they are helpless as it will take nearly two years to organize everything.

Gattis said, "By the time we've finished and then everyone starts gearing up again, it roughly takes that long."

Gattis further said that they originally planned each episode to last for 60 minutes and that each season of the show would comprise just six episodes. However, things changed by coincidence.

"We ended up doing 90-minute episodes by accident and everything would have been different if we had stuck to our original plan."

In the meantime, Martin Freeman, who portrays Dr. Watson in "Sherlock," recently brought some good news for fans when he divulged that producers were planning a special episode of the show.

The British actor said on Alan Carr's Channel 4 chat show, "Mark Gatiss may beat me up, but there is an idea for this one-off special that's such a good idea."

Describing the move as a "mouth-watering idea," Freeman, however, said that he did not have any clue as to when the team will commence filming the special episode.

In previous interviews, Freeman indicated that originally the team planned to commence production of "Sherlock" Season 4 sometime this autumn, but this was not possible owing to the hectic schedule of the creators and lead actors.