"Dark Heart" is the tenth episode of the first season of Justice League Unlimited, and the tenth of the overall series. It originally aired on December 11, 2004.
In the Nevada desert, a large alien construct lands on a mesa in an area which includes three neighboring towns. Huge spider-like robots emerge from the construct and proceed to spread over the area!
With General Wade Eiling in command, the United States Army arrives to try to keep the alien robots from overrunning the region. The army does what it can but their weapons are ineffective against the alien threat. The full force of the Justice League is called in and Batman determines that the construct and the robots absorb local matter in order to grow bigger. Flying in his Batwing, he dumps an ice-bomb on to the structure in order to freeze it. The rest of the League then engage the spider-like robots but before long the machines are numbering in their thousands and are increasing.
To buy time, J'onn J'onzz tells the League and Army forces to pull back, clearing the area for the Watchtower's Binary Fusion Generator, an energy cannon "with the punch of a small nuclear weapon". From orbit, the cannon fires, digging a trench around the mesa to halt the aliens' advance, buying time to evacuate the nearby towns. Using his x-ray vision, Superman then discovers that at the centre of the alien structure is a Dark Heart which is replicated in each of the attack robots.
Since this alien invasion appears to be based on nanotechnology, Batman suggests that they consult the Atom, aka Professor Ray Palmer, an expert in the field. The energy cannon used up so much of the Watchtower's power that they cannot use its teleportation system so Superman flies to Boston where Palmer works in the physics department of a local university.
Superman takes the Atom back to Nevada. By the time they get there, the alien robots have overcome the trench and now number in hundreds of thousands. New robots, in the form of attack dogs, have now joined in the fight, making it even more difficult for the Leaguers to contain the threat. Observing the battle, the Atom explains that the robots can use any kind of matter in order to replicate and repair themselves when damaged and that they will continue until the whole of Earth is consumed! The only solution is for him to get inside the original structure and destroy the core program.
With the support of other flyers, such as Steel, Doctor Light, Green Lantern John Stewart and the Ray, Wonder Woman gets the Atom to the structure where he shrinks down to micro size and goes inside it. At the centre of the construct, Atom accesses its memory and learns that it was a war machine built by aliens as part of a galactic war. It destroyed its creators' enemies but then proceeded to other planets and destroyed them as well as part of its program, unaware that they were not involved in the original war.
Atom himself is attacked by the construct's internal defences, but evades them and eventually finds the Dark Heart's core control. Outside, the Leaguers are being overwhelmed by the robots which have become even bigger and more aggressive to the point that even the most powerful members are finding it hard to fight back. Atom's attempts to destroy the Dark Heart with his fists are in vain. He then notices some tubes that feed the Heart with liquefied matter. By blocking one of the tubes, he causes the liquefied matter to build up, break out of the tube, causing a flash flood which fills the construct and destroys it. Outside, receiving no further instructions from the main Dark Heart, the attack robots shut down and deactivate, moments before they were about to overrun the Justice League.
With the invasion over, the Army gathers up the remains of the Dark Heart. Superman expresses concern for the material falling into the wrong hands, but General Eiling makes it clear that he intends to use it to find a way to counter the Justice League, citing the powerful weapon that they have in the Watchtower pointing down on Earth! Atom fears that if the Dark Heart is reactivated it will also destroy everything on Earth, just as it destroyed everything else it encountered before. Superman assures him that they won't let it.
- This episode reveals the existence of the Watchtower's orbital cannon.
- First appearance of General Eiling. In the subsequent episode "The Doomsday Sanction", he is shown to be working for Project Cadmus.
- The remains of the Dark Heart re-appear in "Divided We Fall" in which Amanda Waller, the head of Cadmus, admits that her scientists are unable to re-activate it.
Home video releases
- Justice League Unlimited - Season One (DVD)
- Justice League - The Complete Series (DVD)
- Justice League Unlimited - The Complete Series (Blu-ray)
- Justice League: The New Frontier (2DVD, Blu-ray only)
- Eiling announces himself as United States Air Force ("USAF"), but appears to wear an Army uniform.
- In an early scene where Green Arrow and Crimson Avenger are fighting the mechanical spiders, Aquaman can be seen coming down a Javelin ramp. He does not appear in any subsequent scenes and is unlikely to have been involved in a crisis which takes place in the middle of the Nevada desert and does not directly threaten the sea or Atlantis.
- Just before he lands with Superman, Batman can be seen on the ground with the others fighting the spiders. Also during the fight Red Tornado is seen firing what appear to be red energy bolts; a power he does not possess.
- Batman's emblem is missing its head when it's first seen and is simply batwings. It vanishes completely when Batman throws batarangs at the attack tigers on the Batwing, though it can be clearly seen almost completely above his harness in the previous and next shots.
- After appearing in the scene noted above, Green Arrow and Crimson Avenger are notably absent from the gathering of the Leaguers in the final scene.
- In this episode, Atom's DCAU base of operations is established as Boston. In the comics, Atom is a superhero/college professor who lives in the fictional city Ivy Town.
- Atom is seen in a petri dish fighting a cell-sized monster (car sized to him). This is possibly a reference to the Frank Miller comic "The Dark Knight Strikes Again" where Palmer is found in a similar predicament.
- This marks the final time in the series where the opening title sequence uses clips from the episode it is featured in.
- Atom mentions the theories of John von Neumann.
- Superman's line before heading into the fray with Wonder Woman and the Atom is a possible reference to the last line of the Buffy spin-off "Angel".
- Final appearance of the Batwing in the DCAU.
|George Newbern|| Superman|
|Carl Lumbly|| J'onn J'onzz|
|Kevin Conroy|| Batman|
|Susan Eisenberg||Wonder Woman|
|John C. McGinley||The Atom|
|J.K. Simmons||General Wade Eiling|
|Michael Beach|| Commander|
|Catherine Cavadini|| Katie|
Billy's girlfriend (uncredited)
Batman: (falling from the sky) Batman to all points. I could use some air support... since I can't fly... at all. (reaching the ground) Now would be good.
Wonder Woman: (fighting robots while holding the tiny Atom in her fist) I need both hands, Professor Palmer!
Superman: (referring to the remains of the Dark Heart) I don't suppose you need any help destroying that? Wouldn't want that technology falling into the wrong hands.
Atom: Amazing. Show him a weapon that destroyed its creators and every other thing it saw, and he wants to play with it. What's to stop history from repeating itself right here on Earth?
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|Cadmus Story Arc|| Next episode:|
"The Doomsday Sanction"