Avengers: Age of Ultron is a sequel on steroids. It is incredibly bloated in some parts, but overall does an admirable job of making what was good in the first film better. Writer/director Joss Whedon had a few boxes to tick to surpass the original's scale, introduce new characters, and stick to the comic's storyline beloved by fans for decades. The result is an epic film that will surprise audiences by its heart. Whedon gives every character quite a bit of exposition, with a little romance and tragedy mixed in to keep the spectacle grounded.

The film opens with The Avengers attacking a hidden Hydra base in the fictional country of Sokovia. They are searching for Loki's stolen staff. They have their first encounter with Hydra's new secret weapons, mutant twins - Pietro (Aaron Taylor-Johnson) and Wanda (Elizabeth Olsen). Possessing super speed and telepathic powers respectively, they pose a difficult challenge; and have a blood vendetta against Tony Stark (Robert Downey Jr.). The team recovers the staff, but their victory lap leads to a catastrophic error in judgement.

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Stark discovers a new kind of artificial intelligence powered by the jewel inside the staff. He dreams of a computer program - Ultron, that can operate his armored suits independently to protect the earth from extraterrestrial threats. Stark convinces Bruce Banner (Mark Ruffalo) to help him, which contravenes Captain America's (Chris Evans) orders and Thor's (Chris Hemsworth) trust. They seemingly fail, until Ultron (James Spader) makes his debut with dramatic flourish. Ultron allies himself with the Maximoff twins. He uses Wanda aka The Scarlet Witch's powers to poison the minds of The Avengers. They must face their greatest individual fears, then unite again to uncover Ultron's wicked plans.

Ultron, surprisingly, is the weak link here. I was expecting an incredibly diabolical and menacing villain. Spader's voice over has a few interesting quips, but there isn't a second where I thought Ultron was a serious threat. In fact, the Ultron battles fall prey to this generic CGI combat that's the new action filler in effects films. The Ultron drones could easily be Chitauri soldiers from the original. They crumple like tin foil, even under the slightest blows. Ultron has a few moves, but I thought Captain America was doing a pretty good job fighting him single handed in a key scene. The Scarlet Witch's spell proves to be a much more dire threat to the team.

The greatest strength of the film is the dynamic between the leads. This is a spoiler free review, but I will say the romance between the Hulk and Black Widow is fantastic. Both actors shine in one particularly dramatic and revealing scene. Another seed change is the emergence of Captain America as the team leader, with Tony Stark being his primary foil. They are uneasy allies. Thor drives key plot elements into the next film with little fanfare. But it is Hawkeye (Jeremy Renner) who proves to be the team's rock solid core. He plays an integral part in keeping the band together. Audiences, after they gasp from that sweet Hulk/Black Widow action, will be equally amazed by what Hawkeye's been doing in his spare time.

The bangs and whistles look great for most of the film. The best fight scene, effects wise, is a knockdown, drag out brawl between the Hulk and Iron Man. It's a mind-blowing sequence that stands out from the repetitive CGI of battling the Ultron drones. I have a feeling that The Hulk Buster costume is going to be a big hit at Halloween.

It's a big film, hugely entertaining, that'll deliver what the audience wants with a few touching moments sprinkled throughout. Some parts seemed like a giant video game to me, but that's the result of so many elements interacting digitally in the sprawling fight scenes. I honestly prefer the superhero genre when it's more grounded. Captain America: The Winter Soldier and Guardians of the Galaxy, were gigantic effects films, but not as expansive with their characters. You also want to stick around after the credits to see the next baddie on deck.

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