'Gotham' Season 4 Trailer Reveals Proto-Batman Suit And Scarecrow
The Scarecrow Returns
The trailer also offers a terrifying glimpse at the Scarecrow (Charlie Tahan).
Jonathan Crane first appeared on Gotham in the show's first season. The episodes "The Fearsome Dr. Crane" and "The Scarecrow" focused on Jonathan's father, Gerald, and his attempts to create a serum that would remove fear from anyone who took it.
Gerald succeeded and dosed himself with the serum and then dosed Jonathan. No longer having fear, Gerald Crane opened fire on the GCPD and was shot dead.
Jonathan overdosed on the serum, which then began having adverse effects on him. He looked up at a scarecrow and began screaming. He was taken to a hospital where doctors discovered that he was being forced to constantly see his worst fear, a sentient scarecrow attacking him.
It seems that Jonathan Crane has made some kind of recovery and is now set to bring his own fear to Gotham City.

Gotham: A License To Kill
Here's the newly released official synopsis for the season four premiere of Gotham:
prevA LICENSE TO KILL
ON THE ALL-NEW SEASON FOUR PREMIERE OF "GOTHAM"
THURSDAY, SEPTEMBER 21, ON FOXGordon fears Jonathan Crane (guest star Charlie Tahan) is still alive and back in Gotham, when The Scarecrow's signature MO is used in a series of robberies. Meanwhile, Penguin's "licensing" of crime in the city backfires during the grand opening of his new Iceberg Lounge. Also, in the aftermath of his encounter with Ra's Al Ghul, Bruce begins his vigilante watch in the all-new "Pax Penguina" season premiere episode of GOTHAM airing Thursday, Sept. 21 (8:00-9:00 PM ET/PT) on FOX. (GTH-401) (TV-PG L)