There are times when playing Origins you'll forget you're playing the portable version - that's how good it is. Do as the game suggests and play with the lights off and your headphones on and it's a supremely atmospheric experience, and one that really showcases what can be done with the PSP hardware with a little effort.
Graphically its an absolute triumph in most areas - whilst the main character of Travis is little bit chunky and low polygon, the environments are wonderfully detailed, crammed with filth and decay and all manner of dark atmospheric touches. The torch is simply superb, casting lovely realtime shadows off the scenery and shambling creatures. Its just gorgeous and brilliantly creepy to explore. Catching a glimpse of something moving in the dark up ahead is a wonderful thing, and when combined with the haunting and eerie soundtrack the whole experience is incredibly compelling, and does a good job of keeping things tense.
Mechanically its all fairly old school, as with the 360 version - locked doors abound in every location, channelling you along an essentially linear pathway towards your goal, but its an enjoyment in itself figuring out the way to go. Puzzles are fairly standard stuff, relying on combing all areas carefully for odd items to be combined - some of the clues are a little cryptic, but generally theres nothing overtly taxing here. Not to say its not satisfying to solve a puzzle and progress, but you won't be needing any pen or paper to make notes.
Combat is fairly slow and considered. Melee weapons whilst fairly common, break within a short time meaning you can never really rely on one particular favourite. Ammo for weapons is generally scarce so the best tactic is often to simply avoid confrontation and run around the nicely animated monstrousities. Certainly when roaming the foggy town, this is the only viable option given the sheer number of mad creatures that lurk in every corner. Melee combat is also given a slightly random twist by allowing you to carry any number of one hit items such as TVs toasters, bottles etc.
Save points are few and far between too and there will be a few unfair deaths as you're assailed by some monster forcing a restart which feels a little unfair. Some areas descend into trial and error, which feels slightly dated but doesn't detract much from the overall experience.
All wonderful stuff then, this is hugely atmospheric and creepy gaming, with some wonderful visuals and engrossing violent exploring.