The arrival of the fourth and final volume of the premiere season of "The Avengers: Earth's Mightiest Heroes" is a bittersweet moment for this lifelong Marvel fan. While the series lives up to and exceeds the expectations built by the preceding 19 episodes, a continually delayed premiere date for the second season and unconfirmed rumors that some influential figures at Marvel want to push the show away from the larger story arc format that made season one the smash hit it is, season one stands potentially as great "what could have been" moment in animation.

Rumors and gloom and doom aside, the last seven episodes of "Earth's Mightiest Heroes" give viewers what was so carefully teased: the revenge of Loki, Thor's wicked brother. Before we get to that, the show runners offer up not just one, but two great multi-episode storylines, which follow on the heels of a Thor centric, (generally) self-contained episode and the long awaited return of the Black Widow to set the record straight, patch up hurt feelings and expose a threat from Captain America's past that forces our hero into a position that once again, sets future events into motion. Fans of the live-action "Thor" and "Captain America" films will particularly enjoy these opening two entries, as key items from both films: the Casket of Ancient Winters and the Cosmic Cube are integral plot points respectively.

A shakeup in the Avengers roll is teased in the two-part Ultron saga, with Ant-Man desiring to walk away from the team, but when his supposedly peacekeeping robot Ultron threatens the world, Dr. Pym is tasked with making the personal sacrifice that has faced every core member of the Avengers at some point in their lives: to borrow from the great Spock, "the needs of the many outweigh the needs of the few, or the one." Veteran Marvel fans will have a wide grin at seeing Ultron come alive on-screen and the animated format of the show lets all sorts of physical impossibilities become reality.

Saving the best for last, Loki reveals himself as the master manipulator of reputation, in the series' final three episodes. The highest complement I could pay this series is to say if another hour of buildup could have been attached to the beginning of this final 60-minute arc, I'd have paid to see this in a movie theater. The climatic threat sends our team across worlds, encountering allies of all shapes and sizes including Thor's mighty Warriors Three. While Loki is not as nuanced as his live-action counterpart, his genocidal plan is far more terrifying and evil.

Not only does the first season of "Earth's Mightiest Heroes" end on a heroic, dramatic, and action filled final note, the final stinger gives yet another hint at possible story arcs for season two. The writing team on the series continues to do the impossible by keeping the dialogue and plotting accessible to a wide range of ages; "Earth's Mightiest Heroes" may air on a kid's network, but that doesn't mean it's a kid's show. It's for all comic fans, young and old, casual and devoted. It's my sincere hope that season two continues in the same vein as season one, there is so much of the Marvel Universe out there to explore and numerous paths to take that were set-up over this 26-episode genesis. The only thing confirmed thus far is the long awaited debut of Dr. Doom, and if he's as written half as well as Loki and Kang were in the second half of this series, season two already has a head start on delivering a better final product.

The 1.78:1 anamorphic widescreen transfer would be reference quality if it weren't for two glaring technical hiccups. A very primary colored series, compression artifacts are occasionally noticeable, resulting in a less than smooth image. Additionally, aliasing is a minor but noticeable issue, and in animation where smooth lines can be key, this is a bit frustrating. That aside, the transfer is strikingly clear and vibrant, with strong clarity.

The Audio

The Dolby Digital English 5.1 audio track is solid, with strong sound design and appropriate usage of the surrounds. Dialogue is well mixed and clear, while action sequences never feel overpowered or underplayed. English subtitles for the hearing impaired are included.

The Extras

As with volume three, the lone extra is "Avengers Unmasked: Hail Hydra," a glorified trivia track for the episode. The catch is the episode is confined to a small box around changing relevant artwork, with little trivia bubbles popping up covering on-screen action in more detail. The older Marvel fan won't find a lot of use out of such common knowledge, but younger viewers who haven't had the ability to explore decades of storytelling on the printed page will find it of value.

Final Thoughts

Of all four volumes, this final release is the strongest in terms of quality, although only by a fraction. It's a release solely for those who have at least volume three (and if you like that, you better have the first two). Now let's just keep our fingers crossed that season two debuts sometime soon and the format is left untouched. Highly Recommended.