After "Sherlock" season 4 concluded earlier this year, there is uncertainty whether the British crime drama spin-off will return for a fifth installment.

It is still uncertain whether "Sherlock" will return for season 5. Benedict Cumberbatch, who plays Sherlock Holmes, and Martin Freeman, who portrays Dr. John Watson in the series, are too busy to work on another installment.

Aside from them, Sian Brooke, who plays Sherlock's sister Eurus Holmes, has been cast in "Mission Impossible 6," making it also difficult for her to juggle her time in case the television series continues with a fifth iteration.

Nonetheless, fans are still not giving up on convincing the actors and the people behind the show about "Sherlock" season 5. Earlier this week, a Twitter page has been put up to call all fans to convince the producers to work on a new season.

On the social media page, it says, "Passionate about #Sherlock? Want more? Make your voice heard! Parallel fandom of old & help trend #Bring221Back in a quest for more content."

The content compares the instance in the past when author Sir Arthur Conan Doyle was "accosted in the streets by fans who refused to accept their beloved detective was gone for good." The Twitter post convinces fans to do the same in a 21^st-century manner, specifically through social media.

The Twitter post encourages fans to make the hashtag #Bring221Back trending on Sunday, April 2, from 8 p.m. to 9 p.m. UK time, or 3 p.m. to 4 p.m. EDT, in the hope that it will catch the attention of the producers and the actors and bring a fifth season of the television show. 

Meanwhile, fans who want to watch "Sherlock" from season 1 to 4 will be able to do so soon. According to reports, AXN will air the show starting from "A Study in Pink" to "The Final Problem" every Sunday at 12 p.m. onwards starting on April 2.