Metropolis is a grand high-tech city-state populated by humans and robots alike. It is in these streets that Detective Shunsaku Ban and his sidekick Kenichi search for the rebel scientist Dr. Laughton who unbenounced to them, is developing a super android named Tima as a tool for the Duke of Metropolis. What starts out as a normal case turns into mayhem as the scientist is murdered, and the true plans of the Duke are finally revealed...
Dr. Tenma is obsessed with creating a robot with a soul, so much that he forgot to care for his own son Toby; and when Toby is killed in a car crash, Dr. Tenma is overcome with grief and models his next robot, who has a soul, after his dead son. Things quickly take a turn for the worse as Toby is not accepted into society; and Dr. Tenma, angry with the fact that Toby is a robot who can't replace his son, drives Toby into the clutches of the evil owner of a robot circus, the place where he earns the name Astroboy. Astroboy is rescued by Dr. Elefun, Dr. Tenma’s successor, after his disappearance. From then on Astroboy has to struggle to be accepted into a society that views robots as inferior to humans, while fighting to protect them in turn. With the help of Dr. Elefun, Astroboy has to find his place on Earth and gain confidence in his own powers – all to become the greatest hero ever.
Both being made by Ozamu Tezuka, both work's worlds deal with the interactions of humans and robots. And just like one another, Tima and Astro were brought into a world that could have easily ended for them or continued in tragedy due to the cruelty of people who injusticed against them due to their own wants of domination.
After a horrific car crash, Dr Tenma lost his beloved son Tobio. Out of grief, he built a robotic son named Astro as a replacement; but soon after, Dr Tenma had the boy deactivated and put into a deep sleep. In the present, the scientist Dr O'Shea finds Astro and risks everything to reactivate him, train him to be a hero of justice, and raise him to be a functioning member of society. Amidst the prejudice of humanity, the pacifistic Astro will promote peace, battle the forces of injustice, and attempt to bridge the gap between humans and machines.
Both these shows were the creation of Osamu Tezuka - in fact, the original Metropolis manga produced in the 40s was a prelude to themes and philosophies he would latter develop in the wildy popular Astro Boy corpus of work.
The main (robot) protagonists, Astro (Tobio) and Tima, both have similar backgrounds: they are built as 'replacements' for lost relatives by their creators, they are both 'cutting edge' in terms of AI, blurring the line between humans and robots. Both robots were also created to serve a 'higher purpose' for their creator which serves as a central plot point.
The artstyle remains faithful to the Tezuka style, and his 'star system' (where characters are not restricted to certain series, but 'act' in multiple, unrelated stories - provide cameos if you will) is in place. Duke Red, Rock, Boon and many more of Tezuka's characters make appearances in both Metropolis and Astro Boy.
In short - same creator, same themes, same characters - subtle differences in approach and story.
*Recommendation for the 2003 Astro Boy series as this one follows Tezuka's concept more closely than the 60s and 80s series.
One year has passed since the Crisis. People have come to believe that peace has been restored, but they were wrong - violence strikes the neighborhood once more and it all seems like a bad case of déja vu: the Boomers are back. But this time, there's something strange about the crime wave - highly advanced computer components are disappearing at the same time. The question is, who is the puppet master behind all this, what does he want, and what is his purpose?
The year is 2032. Tokyo has been destroyed by a great earthquake and a new city, MegaTokyo, has risen from the ashes. Humans now live side-by-side with androids known as Boomers who perform many of the menial and laborious tasks that humans despise, but these artificial servants come with a price: they have a tendency to go haywire and attack those they were built to serve. The A.D. Police force was created to try and stop this menace, but its weapons can do little more than annoy the Boomers. Hope lies with the Knight Sabers, four young women with high-tech, armored suits and enough firepower to stop an army - but will it be enough to stop MegaTokyo's greatest threat?
Having failed to earn admission to a university, Hideki Motosuwa has moved to the big city, determined to study his hardest for next year's exams. However, an unusual distraction presents itself one unsuspecting day in the form of Chii, a robotic young girl that has been discarded in the trash. In a world where an increasing number of people turn to these 'persocoms' for company, the bonds and limits of human relationships are tested as flesh manages to fall in love with the machine itself...