By Alfred Hermida BBC News Online

The men who protect the Earth from the scum of the universe are back and they have a lot to live up to.

The original Men in Black (MIB) was a phenomenal hit when it burst onto cinema screens five years ago, grossing $587m worldwide.

The sequel reunites the alien-busting futuristic cops played by Will Smith and Tommy Lee Jones for another mission to save the planet.

In many ways, this is the perfect summer blockbuster - a paper-thin plot packed with gags and special effects.

Memory lapse

Men in Black II picks up where the original left off. Tommy Lee Jones, Agent Kay, has had his memory erased and retired to a quiet life running a rural post office.

Lara Flynn Boyle: Alien seductress

Faced with a new threat from aliens, Will Smith (Jay) must restore the memory of former partner Kay, whose brain contains the necessary information to thwart the enemy and save the universe.

And that is basically it, as far as the plot goes. In a way it does not matter. The film is a rapid stream of jokes and gags, involving rubbery, bumbling aliens.

For the sequel director Barry Sonnenfeld has taken few chances. As well as Smith and Jones, Rip Torn returns as Zed, the boss of the Men in Black, the secret unit that monitors extra-terrestrial activity on Earth.

And a couple of the aliens which got some of the biggest laughs in the original are given more screen time this time around, such as Frank, the cigar-smoking, tough-talking dog and the sleazy Worm Guys.

Lingerie model

This time, the enemy is a sinister alien seductress called Serleena, played by Lara Flynn Boyle.

Rosario Dawson: Love interest

She plays a hydra-headed monster, disguised as a rather more eye-pleasing lingerie model.

And there's even a bit of a love interest for Smith in the shape of Rosario Dawson.

The film moves at a brisk pace, coming in at a trim 88 minutes, so the movie does not outstay its welcome.

As you would expect, the technical effects are top-notch, though the alien creatures do look ridiculous. That is part of the joke.

If anything the film lacks the freshness and spark of the original MIB. Essentially it recycles a successful formula for what will doubtless be a summer hit.

Men in Black II is released in London's Odeon, Leicester Square on Thursday 1 August and in cinemas across the UK from Friday 2 August.