Doctor Alchemy

Doctor Alchemy is a name used by three different supervillains appearing in American comic books published by DC Comics. The most notable was Albert Desmond, who originally used the name of Mister Element.

The character appeared as a recurring cast member on The CW television series third season of The Flash played by Tom Felton. The character makes his cinematic debut in the DC Extended Universe film The Flash, played by Rudy Mancuso.

Publication history
The character of Albert Desmond, created by John Broome and Carmine Infantino, first appeared in Showcase #13 (April 1958) as Mister Element. His second, and more frequently used, identity of Doctor Alchemy first appeared in Showcase #14 (June 1958).

The Alchemist made his first appearance in The Flash (vol. 2) #71 (Feb. 1992) and was created by writer Mark Waid and artist Greg LaRocque. The character of Alexander Petrov made his first appearance in The Flash (vol. 2) #202 (Nov. 2003) and was created by Geoff Johns and Alberto Dose.

Albert Desmond
Albert Desmond  is a lowly chemist who suffers from dissociative identity disorder. Desmond has two distinct personalities: one major driving personality and another criminally inclined one. Under his darker personality, he applies his knowledge of chemistry to create the identity of Mister Element. He creates elemental weapons such as bulletproof silicon to shield his cars, and discovers a new element, Elemento, a magnetic light with which he sent the Flash into space.

After being sent to jail as a result of his first encounter with the Flash, he learns of the Philosopher's Stone from his cellmate. He escapes jail, finds the Philosopher's Stone, and uses its power to transmute elements to restart his criminal career under a new identity – Doctor Alchemy. Eventually his good personality resurfaces, causing him to quit crime and hide the Philosopher's Stone. Shortly after, a new Doctor Alchemy appears and is revealed to be his astral twin "Alvin" Desmond, with whom he shares a psychic link. It was later revealed that "Alvin" was a construct of the Stone created by Albert's criminal personality. When Albert confronts and defeats "Alvin", he resumes the identity of Doctor Alchemy. While he was incarcerated, both of his costumed identities were used by others: Curtis Engstrom using the Philosopher's Stone as the Alchemist and Alexander Petrov using the Mister Element identity.

Curtis Engstrom
Dr. Curtis Engstrom is an advisor on the project when S.T.A.R. Labs acquired the Philosopher's Stone with intentions of using one of its fragments in their microscopic medical computer. He stole the computer with the help of a small-time crook, Moe "Mouthpiece" Miglian, but he was later arrested. After escaping from prison, Engstrom donned his own Dr. Alchemy costume and set out to retrieve the microchip that had been taken from him by Miglian, calling himself the Alchemist. After being defeated, Engstrom and Miglian were both sent to prison.

Alexander Petrov
Alexander Petrov is a criminologist working for the Keystone City Police Department. But in order to advance his career, he uses one of Albert Desmond's weapons used as Mister Element to freeze the lab supervisor solid. Petrov is promoted to replace the dead supervisor and discovers he likes the thrill of killing. He continues to eliminate members of the department he sees as "threats" to his position, using the weapon and ice-based effects. He uses the effects and his position as head of the crime lab to shift suspicion to Captain Cold. His plan comes undone when profiler Ashley Zolomon enters his office as he is putting on his mask. The Flash is able to stop him from killing Zolomon, but Captain Cold interrupts them before the Flash can take him into custody. Captain Cold kills Petrov for breaking one of the rules of the Rogues' code of "ethics" – never frame another Rogue for your own crimes.

Powers and abilities
As Mister Element, Desmond dons a suit equipped with an oxygen mask and selects the model of carbon as his suit emblem. Doctor Alchemy possesses the Philosopher's Stone which once belonged to Merlin. By pressing the stone in various points, he has the ability to transmute any substance into any other substance (e.g., steel into rubber, or oxygen into carbon monoxide) and also possesses the power to transform the molecular structure of the human body, having once turned the Flash into a being of water vapor. Albert Desmond can also control the Philosopher's Stone from a distance via telekinesis.

Television

 * Doctor Alchemy and Mister Element make non-speaking cameo appearances in the Justice League Unlimited episode "Flash and Substance".
 * Julian Albert Desmond / Doctor Alchemy appears in the third season of The Flash (2014), portrayed by Tom Felton and voiced by Tobin Bell. This version is a British forensic scientist, Barry Allen's rival in the Central City Police Department (CCPD), and was created by a time aberration caused by the creation and erasure of the "Flashpoint" timeline. In the past, Desmond led an archeological team to locate the philosopher's stone, intending to use it to resurrect his dead sister. While Desmond finds the stone, his team was killed and he began to experience blackouts, during which he was called upon by Savitar to become his servant "Alchemy" and use the stone to restore metahumans from the "Flashpoint" timeline. Eventually, Desmond is apprehended by Allen and Jay Garrick, who discover his identity and use him to contact Savitar via the stone. After being saved from Savitar, Desmond makes amends with Allen and briefly joins Team Flash to defeat Savitar before moving back to the United Kingdom.

Film
Albert Desmond appears in The Flash (2023), portrayed by Rudy Mancuso. This version is a member of the Central City Police Department and co-worker of Barry Allen and Patty Spivot. Additionally, an alternate reality variant of Desmond who became Allen and Spivot's roommate makes a minor appearance.