An animated adaptation of the radio drama was created for Mewtwo Strikes Back - The Kanzenban, the special version of the first movie created in preparation for the film's North American release. It debuted in Japan on July 8th, 1999 when TV-Tokyo aired mewtwo Strikes Back - The Kanzenban during a two hour special to promote the new movie Revelation Lugia.


While the adaptation hits most of the high notes of the story, it is still heavily condensed; the radio drama is, altogether, about an hour long while the animated adaptation is only about ten minutes. Some of the changes made include:

• The entire first episode of the radio drama is skipped over completely. Likewise, all of Miyamoto's reports at the end of each radio episode are removed as well.
  
• The professor who creates Mewtwo is known in the radio drama as Dr. Fuji (フジ博士), but everything else - the actual movie itself, the animated adaptation of the radio drama, all the promotional materials and guide books for the movie - refers to him simply as "professor" (博士).
  
• Sakaki does not make an appearance in the animated adaptation. While it's clear that Dr. Fuji works for the Rocket-Dan in the radio drama, the professor's connection to the organization can only be inferred in the animated version. Sakaki is also never brought up in the Japanese version of the short, though the English version does add a bunch of lines that explicitly connect the two.
• The cloned Pokémon - Fushigidane, Zenigame, and Hitokage - actually say the word "two" as part of their Pokémon cries in the radio drama. Their animated counterparts do not.
  
• The cause of Ai's death (a car accident) is never revealed in the animated adaptation.
  
• In the radio drama, Dr. Fuji's wife leaves him before Ai's death while in the animated adaptation she doesn't leave until after she passes away.
• The Copies that Dr. Fuji's made are not able to last longer than four years, implying that the professor's been at this whole cloning business for quite a while. None of this information is given in the animated adaptation.
• Young Mewtwo was recast for the animated adaptation. In the radio drama, young Mewtwo is voiced by Fujiko Takimoto (瀧本 富士子) but is voiced by Shoutarou Morikubo (森久保 祥太郎) in the animated version.
  
• Ai spends more time teaching Mewtwo various words / phrases in the radio drama than she does in the animated adaptation.

The final two episodes of The Birth of Mewtwo retreads material that's in the actual movie, though there are some differences here as well.

• As Mewtwo continues to grow, its psychic powers start to break various equipment around the lab. This causes the lab's computer to identify it as a threat and therefore take actions to eliminate it. A laser beam is fired at Mewtwo that effectively kills it for a few seconds. Before long, however, Mewtwo's life signs return as the Pokémon displays its ability to regenerate itself. Mewtwo then identifies the computer that attacked it and destroys it with its psychic powers.
• The attacks that Mewtwo can use in the radio drama are identified as Psychic Power ("Confusion"), Sleep Paralysis ("Disable"), Speed Star ("Swift"), Psychokinesis ("Psychic"), Self-Regeneration ("Recover"), and Hyper Beam ("Hyper Beam").
• When Mewtwo is working for the Rocket-Dan, it is implied that it captures the Fushigibana, Kamex, and Lizardon that would eventually be cloned and used to battle the trainers on New Island.
  
• In the radio drama, Sakaki has a trainer's Boober captured in a Monster Ball despite the numerous examples present in the animated series showing that this should be impossible.
  
• At the end of the radio drama, Mewtwo states that it has never shed tears, alluding to a comment made at the beginning of Episode Four (and at the end of the animated adaptation) that it had forgotten all about Ai and the cloned Pokémon.
  

This may seem like a lot, and I guess it kind of is, but despite all this I still feel like the animated adaptation is pretty faithful. A lot of the dialogue is kept word for word, and the overall themes and ideas present in the radio drama are still there. I still recommend checking out the audio version because it does contain a lot of really great detail, but if you can't for whatever reason, then the animated version is not a bad way to go.
Despite the fact that the animated adaptation was made for the Kanzenban, which itself was made for the North American release of Mewtwo Strikes Back!, the full short never actually aired in American theaters.  I unfortunately don't have a copy of the Region 1 DVD with me right now, but from what I've heard / remember, only the first scene with the explorers going into the jungle and finding the Mew fossil was kept. Everything dealing with young Mewtwo and Amber was cut.

Pokémon The First Movie was released in theaters in the U.S. on November 10th, 1999.

In Japan, the animated adaptation was released on DVD on June 23rd, 2000. This bilingual DVD contains the full English dub of the animated short, meaning that an English version of "The Birth of Mewtwo" existed at least as early as that. Did 4Kids dub the short and then decide to cut it at the last minute? It's possible. Maybe 4Kids thought kids wouldn't want to sit through so much backstory before getting to see Ash and his friends, and maybe they were worried that the content of the story was too dark for them to retain the movie's G rating.


The full, uncut version of "The Birth of Mewtwo" was finally released in the U.S. on December 4th, 2001 with the release of "Mewtwo Returns" on DVD, about a year and a half after the English dub was released in Japan.

In Japan, "The Birth of Mewtwo" was added to the beginning of the first movie and has essentially become the first ten minutes of mewtwo Strikes Back! The English version, on the other hand, has never been attached to the film and is instead treated as a standalone short.

Unfortunately, the CD The Birth of mewtwo has been out of print for a decade and a half, so finding it can be a bit tricky. The CD set will pop up on Amazon and e-bay from time to time, so I would advise checking those sites periodically to see if anyone's selling them. The set will probably be a bit on the pricey side, but it is absolutely worth it to be able to experience one of the most fascinating tales ever told in this franchise.