Let me put this simply - if you don't get caught up at least a little bit in the simple gameplay and infectious fun of Loco Roco, then either you are dour and cynical, you have no soul, or perhaps should check your pulse. This is not the best or most innovative game on the PSP, but it is so full of fun and simple joy that you owe it to yourself to have a play - and once you do, the addictive gameplay will pull you back in time and time again.

Loco Roco does have a story - or at least a premise. A happy and peaceful world is attacked by dark clouds that threaten to destroy the happy inhabitants. You are the Loco Roco tasked with saving as many of the inhabitants as possible, in various areas of the four different game worlds. The game is essentially a two-dimensional, side-scrolling action game, but it's much more reminiscent of the Katamari games in terms of play style and art design.

Playing the game couldn't be much simpler - you use the L and R shoulder buttons to tilt the world to the left and right, while pressing both buttons to jump, although bounce might be more accurate a term. As you move through the stages, your primary task is to collect as many items as possible, as quickly as possible. This includes small blobs that add to the size of the Loco Roco, of which there are twenty per level, while there are also smaller blobs, plus the small inhabitants you need to rescue. They are so happy to see you that they reward you with a Loco Roco house piece - which is part of a mini-game outside of the main story.

The charm and fun of this game comes largely from the infectious style of the graphics and music. The graphics are simple and not very detailed, but they are very bold, colourful and effective. It's amazing how well the physics modelling is done - if you bounce off of a hemispherical platform, your trajectory follows the expected path, slowed or accelerated appropriately as you tilt the world one way or the other. In areas where you know there is something useful hidden just a couple of platforms above you, it is good to know that you are fighting against your knowledge of how to control the world, instead of fighting the controls of other arbitrary game-imposed dynamics.

Whether or not you like popular music in general and Japanese popular music in specific, you will love the songs of Loco Roco. When you come upon one of the sleeping suns or clouds along the way, you will hope that you have collected enough of the small blobs so that your Loco Roco splits apart and begins singing. Besides hearing the fun tunes, these songs also wake the sleeping creatures and unlock a new path or Loco Roco house part. Also, each Loco Roco has different sounds and songs, and you will likely find a favourite to play more often than the others. From beginning to end, the songs and sounds are a constant pleasure to listen to you and a big factor in propelling you to keep on playing.

There are also some mini-games available - aside from the Loco Roco house game, there are a few others, including one resembling an arcade 'prize claw' game, where you pay a few of your collected fruits in an attempt to gain additional items for your house. You can also share these mini-games with others, using the PSP's local WiFi networking for a bit of extra fun.

Yet for all of the simple pleasures, this game is not perfect. First, it is too short, lasting only a few hours from start to finish. That is not necessarily bad, because the appeal of the game is not about a long set of levels, but just the sheer joy of playing. However, even going back and finding every secret, every hidden area and every last piece of fruit that is available, you will exhaust everything the game has to offer in well under a dozen hours. The mini-games are a small diversion that adds little to the overall experience, while the core gameplay is very single-minded, limited to doing pretty much the same thing over and over again. You will either love or hate Loco Roco within the first few minutes of playing it, and nothing that happens later on will change your initial opinion.

Loco Roco is a game that PSP owners simply must try; it's the type of unconventional and quirky gameplay that is infectious and addictive beyond rationality, and a game that you will want to keep playing and never stop - you will want to hear those songs again and again, and to see the different levels using different Loco Rocos. You may not play it for months at a time, but the compulsive gameplay will keep you coming back to it over and over, never letting the game far from your PSP.

Reviewed by Michael Anderson for AceGamez (All Rights Reserved).