Scarecrow (Cillian Murphy)

Batman Begins Time Frame
The Scarecrow appears much like his comic counterpart, this version of the Scarecrow is a corrupt, sadistic psychiatrist specializing in psychopharmacology at Arkham, secretly allied with Ra's al Ghul and Carmine Falcone, smuggling the former's hallucinogenic drugs into Gotham to create fear gas to use upon his patients in cruel experiments. He first appears in the film as Dr. Jonathan Crane, testifying in court that Victor Zsasz, one of Falcone's assassins, is legally insane and should be moved to Arkham for rehabilitation. This enrages Assistant District Attorney Rachel Dawes, who later accuses him of being corrupt. Crane then meets with Falcone to discuss having her murdered. When Falcone later attempts to blackmail Crane, Crane dons his Scarecrow mask for the first time in the film and douses Falcone with his fear gas, driving the mob boss insane and leaving him repeatedly uttering "scarecrow". Crane attributes this to him identifying the image with a Jungian archetype.

In Crane's first encounter with Batman, he sprays Batman with his fear toxin and sets him on fire, though Batman narrowly escapes with his life and mind intact. With the help of Lucius Fox, Batman acquires an antidote to the toxin. Shortly thereafter, Batman has a second confrontation with Crane, this time at Arkham, where he must rescue Rachel Dawes after Crane has sprayed her with his toxin. Batman overpowers Crane's henchmen and sprays the doctor with a dose of his own medicine, destroying what's left of his sanity and divulging his real superior: Ra's Al Ghul. Crane is subsequently arrested by James Gordon, but later escapes in the mass release of Arkham inmates prompted by Ra's Al Ghul as part of his plot to destroy Gotham. As Ra's Al Ghul unleashes Crane's fear gas on Gotham's slums, Crane, now calling himself Scarecrow, pursues Rachel and a boy through an alley on a horse, dragging a dead mounted police officer from its stirrups. To the boy, who was affected with the gas, Scarecrow appeared as a deep-voiced monster riding a fire-breathing horse. After he spouts the quote "You Have Nothing To Fear, But Fear Itself", Rachel eludes Scarecrow by shocking him in the face with a taser. Scarecrow aimlessly rides off into the night, screaming in pain. In the film's final scene, Gordon reveals that Crane is still at large.

Crane wears a mask, seemingly a poorly-stitched burlap sack with a hangman's noose dangling around the neck. The mask has a built-in rebreather and acts as a gas mask, and enhances the effect of the hallucinations in his experiments. The mask is put to good use when a victim is poisoned, making his appearance all the more terrifying to the victim (Batman hallucinates bats flying out of the "mouth", while Rachel hallucinates worms growing from it). He also wears an unbound straitjacket at the movie's climax due to his incarceration in and breakout from Arkham Asylum. Cillian Murphy explained that the relatively simple mask was done because, "I wanted to avoid the Worzel Gummidge look. Because he's not a very physically imposing man, he's more interested in the manipulation of the mind and what that can do."