General Calvin Swanwick was a United States Army general overseeing the defense against General Zod, and later became Secretary of Defense.
Man of Steel
General Swanwick was alerted to the Kryptonian invasion by General Zod's global broadcast demanding that humanity give him Kal-El, who soon came to the U.S. military base with the intention of cooperating as necessary for humanity's safety, being questioned by Swanwick.
Swanwick and the military later assisted Superman and others in stopping the invasion by sending the Black Zero back into the Phantom Zone.
Following the battle, Swanwick sent out drones to keep track of Superman's whereabouts, but Superman immediately destroyed them while insisting that the United States and humanity had nothing to fear in him and telling Swanwick that he trusted him to help convince his government employers of this much.
Batman v Superman
Swanwick, now acting as Secretary of Defense, was initially turned against Superman along with much of humanity following the massacre in Nairomi for which he was framed, but was convinced by Lois Lane to examine a suspicious bullet used in the attack, whose manufacture was ultimately traced to Lex Luthor, thus implicating him as responsible.
Upon Luthor's creation of Doomsday, Swanwick led the initial military response to the monster, and unsuccessfully protested the U.S. President's decision to use a nuclear missile against both Doomsday and Superman.
Swanwick was later present at Superman's funeral.
Zack Snyder's Justice League
As what appeared to be Martha Kent exited Lois Lane's apartment, "she" was revealed to be a shapeshifting alien, which then assumed the form of Calvin Swanwick while muttering that the world needs Lois Lane as much as it needs Superman.
Following the death of Steppenwolf, the alien, in his true form, visited Bruce Wayne to warn him that Darkseid would attack Earth again and that he would help the Justice League fight him when the time came as well as find the Anti-Life Equation before he could, introducing himself as the Martian Manhunter (one of many names he said he was known by).
Powers and Abilities
- Martian Physiology: The average Martian possesses the potential for the following power set:
- Shape-Shifting: Martians have psionic control of their physical for down to the molecular level. This allows them to a form of shape-shifting that allows them to mimic other forms, elongate aspects of their body, increase or decrease their physical size, and so on.
- Invisibility: Martians can cause the biopolymers in their bodies to lose their ability to reflect light, making the Martians invisible to normal light and human sight.
- Phasing: Martians can go through solid matter.
- Superhuman Strength: Martians possess vast levels of superhuman strength and are among the few races that are able to match Kryptonians in terms of raw strength. Martians can easily shatter reinforced concrete and steel, lift and carry houndreds of tons with ease and deliver incredible damage with their blows.
- Superhuman Stamina
- Superhuman Durability: Martians possess high levels of durability that make them nigh-invulnerable to all forms of damage. Martians can withstand high caliber bullets, powerful energy blast and kinetic impacts without suffering damage.
- Superhuman Speed: Martians can process thoughts, move, and react at incredible speed, being able to cover vast distances in little or no time, catch bullets in mid flight, run on water and create afterimages as they run.
- Regeneration: Martians have powerful regenerative powers that enable them to regenerate their entire body from a severed limb, they can furtherly enhance their regenerative powers by drawing mass from nearby sources.
- Extrasensory Input
- Super Hearing
- Heat Vision
- Martian Vision: Martian visual acuity greatly exceed human norms and allows for a wider range of information to be observed. This includes the following:
- Telepathy: Martians have the ability to read the minds of others and project their thoughts to varying degrees. They can also project their mental essences into a gestalt community known as the "Great Mind". Through this, the community can enhance the telepathic strength of other Martians. This power can also enable them to reverse the effects of amnesia or psychological brainwashing. 
- Astral Projection
- Mind Control: As an extension of this, Martians can also use the ability to alter a psychological profile of a target, enabling them to manipulate, and in some cases, outright control that individual. This practice is greatly discouraged however, and only rarely used. 
- Telepathic Relay
- Telepathic Assault
- Telekinesis: Martians have mind-over-matter abilities and can lift and move objects with their minds. They can also employ their telekinesis in offensive way by discharging telekinetic blasts capable of great concussive power.
- Calvin Swanwick was portrayed by Harry Lennix.
- Prior to his departure from the DC Extended Universe, Zack Snyder intended for General Calvin Swanwick to be revealed to be a disguised Martian Manhunter in Justice League. The director's cut of the film restores this reveal in full, but Snyder has confirmed that his cut is non-canon for Warner Bros. Entertainment, Inc.
- If the gap between Man of Steel and Batman v Superman: Dawn of Justice is indeed three years from 2013 to 2016 just like the years where the movies were released, Swanwick's transition from active service Lieutenant General in the United States Army to Secretary of Defense raises questions. The National Security Act of 1947 prohibits active-duty military personnel to serve as United States Secretary of Defense. They are only allowed to do so seven years after retiring. Both the house of Representatives and the Senate would have to have granted General Swanwick a waiver so he'd be able to serve as the Secretary of Defense within this short timespan.
- 3 Appearances of Calvin Swanwick (DC Extended Universe)
- 4 Images featuring Calvin Swanwick (DC Extended Universe)
- 1 Quotations by or about Calvin Swanwick (DC Extended Universe)
- Character Gallery: Calvin Swanwick (DC Extended Universe)
- Martian Manhunter (Volume 4) #1
- Detective Comics #225
- Martian Manhunter (Volume 4) #2
- Martian Manhunter (Volume 3) #3
- JLA #3
- Martian Manhunter (Volume 2) #8
- Martian Manhunter (Volume 2) #3
- DC Comics Encyclopedia: Updated and Expanded
- Who's Who: Update '88 #2
- Martian Manhunter #4
- Detective Comics #226
- Martian Manhunter (Volume 3) #8
- "Zack Snyder Says Martian Manhunter Was In Justice League Theatrical Release" - CBR
- Milheim, Russ (10 March 2021). Justice League: Zack Snyder Admits Joss Whedon Movie Is DCEU Canon. The Direct. The Direct.