"Sherlock" Season 4 was rumored to feature another BBC actor Tom Hiddleston following a recent important meeting between the "Thor: Ragnarok" star and Sherlock's lead actor Benedict Cumberbatch.
A newly released trailer for "Sherlock" Season 4 hints the viewers of the TV series to what looks like a grim and dark season coming next year. The detective show will offer more exciting storylines to its viewers.
