After a lengthy hiatus, the fan favorite series "Sherlock" finally returned for a fourth season this January. The three-episode season reunited Sherlock (Benedict Cumberbatch) and Watson (Martin Freeman) onscreen, and brought in plenty of viewers too.

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But the fourth season (which consisted of the episodes "The Six Thatchers," "The Lying Detective" and "The Final Problem") may have been "Sherlock's" last. At least that's what co-creator Mark Gatiss said while attending the WhatsOnStage awards in the U.K.

As reported by The Sun, Gatiss said, “I honestly don’t know if there will be any more. It’s incredibly difficult to get Benedict and Martin’s diaries to align. And obviously we left it in a very happy place...If that’s the end I’d be very happy where we left it.”

Both Cumberbatch and Freeman's schedules have gotten considerably busier since "Sherlock" launched in 2010. Since that time, both actors have seen their profiles raised due to roles in major franchise films. Freeman took on the lead role of Bilbo Baggins in the "Hobbit" trilogy, beginning in 2012. Cumberbatch played Khan in 2013's "Star Trek Into Darkness" and then joined Freeman in the "Hobbit" as the voice of Smaug. Both actors joined the Marvel Cinematic Universe in 2016, too; Freeman played Everett K. Ross in "Captain America: Civil War" and Cumberbatch played the lead role in "Doctor Strange." Both actors now have extensive commitments with the Marvel Universe, as well. Freeman is currently filming Marvel's "Black Panther" in Atlanta, and Cumberbatch will return as Strange in "Thor: Ragnarok" and "Avengers: Infinity War."

If this is the end of the road for "Sherlock," hints were already placed in the most recent episode. CBR's Lauren Gallaway noted as much in her recap of "The Final Problem," which you can read here.

(via We Got This Covered)