Pity poor "Pacific Rim," coming out right after Syfy's "Sharknado," which has established itself as the Marine Monster Movie of the Summer.

Why did a TV flick with pre-green-screen production values about shark-filled tornadoes striking Los Angeles generate so much attention? The same reason "World War Z" got so much heat -- because they are essentially the same story.

Something terrible happens
WWZ: Unknown force makes people crazy
SN: Unknown force makes sharks crazy

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With roots in social concerns
WWZ: Our fear of a global pandemic
SN: Our fear of global warming

It quickly spreads
WWZ: Internationally, through ports and airports
SN: To Los Angeles, through waves and tornadoes

One handsome man takes the lead
WWZ: Gerry, played by Brad Pitt
SN: Fin, played by Ian Ziering

He has a wife to protect
WWZ: Mireille Enos
SN: Tara Reid

And an attractive but non-romantic female partner
WWZ: Israeli soldier played by Daniella Kertesz
SN: Waitress/bartender played by Cassie Scerbo

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Gridlock is a problem
WWZ: Gerry's family car is attacked by zombies in Philadelphia
SN: Fin's car is attacked by sharks on the 405

Mass transit, however, is not a good idea
WWZ: A whole plane is taken down by zombies
SN: Kids on a school bus are threatened by sharks

It seems nothing will stop the madness
WWZ: Zombies swarm over walls in Jerusalem
SN: A shark eats through the top of an SUV

Until a weak spot is discovered
WWZ: The zombies aren't interested in sick people
SN: The sharknado's can be stopped by home-made cherry bombs

The hero must risk all
WWZ: Gerry injects himself with a dread disease
SN: Fin goes chainsaw first into the guts of a really big shark

Because nothing can thwart real love
WWZ: Movie ends with Gerry reunited with his family
SN: Movie ends with Fin reunited with his family.

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