Obviously not having felt like I'd taken enough punishment by completing the first, I ordered the sequel to Trauma Center: Under the Knife so that it would arrive in time for playing on the plane over to Los Angeles and back. It ended up being just about the perfect length, as I completed it at the end of the holiday after about 12 hours gameplay time (excluding the bonus missions - those are an entire post to themselves). I won't give any specific storyline spoilers here, but I am going to describe some of the new operations in the second half, so you might not want to read that if you want to be as nastily surprised as I was.

As far as mechanics go, much of what I said about the first game still applies. It's difficult to really say without knowing what newcomers think of it, but I think that this sequel strikes a decent balance between leading on from the first game and starting off easy enough for new players to cope with - three difficulty levels have been provided this time rather than leaving you on one, so if you find things too overwhelming then you can switch to Easy, or alternatively bump it up to Hard if you're a total masochist. Slightly disappointingly, the difference between these difficulty levels seems to be purely mathematical - on Easy damaging events are toned down and you can heal really quickly, and on Hard your patient will rapidly die from a mild bruise and you'll get repetitive strain injury from going back and forth with the wimpy stabilizer trying to prevent it. If they'd instead changed the behaviours of some of the stuff you're up against slightly depending on the difficulty level (see my more detailed suggested technique!) then they could effectively have tripled the number of operations in the game - still, there are already a few more than there were in the original, so there's no real reason to complain.

Don't panic, it's nothing a splash of antibiotic gel won't fix

The presentation has had a complete overhaul, to get closer to the games that were released on the Wii - the characters now look completely different due to a new graphics artist, and things look generally more crisp. The music has been changed from something reminiscent of Bill Bailey's version of the BBC News theme to a variety of different styles, mostly somewhere around Metal Gear Solid meets the title music from Casualty. I quite like the soundtrack in general - usually the music is something I pay a lot of attention to in games, but I hadn't really noticed how good this series' was until after finishing the first one. Perhaps mostly because you really don't have a lot of time to listen to it. In other changes, they've happily realized the insanity of having separate modes for the storyline and replaying old operations, so have combined them into one big storyline list, where you can re-watch entire chapters or just do the operations from them. The largely irrelevant miss limit (you had about twenty chances and were likely to lose a maximum of two of them per operation) has also sensibly been replaced with a maximum chain scoring system.

The dialogue isn't completely text-based like the first game, but because they have to work within the limits of a 64MB cartridge, they've only gone for sort of semi-voicing the game, giving each character a few phrases that are spoken out loud on vaguely appropriate paragraphs of the written text - if you're reading through it at a reasonable pace, it gives the impression that the Caduceus members communicate with each other by sort of Twittering verbally in a stream of "Hey." "Excuse me." "Well..." "Yes." "What the..." "Doctor?" "Understood." And it's enormously irritating (apart from the villain's maniacal laugh sound clip, which makes it all worthwhile) but you shouldn't allow yourself to turn it off because the same little sound cues are so helpful during the operations - it's just about possible now to go through it without looking at the top screen at all because you're prompted to do everything verbally.

Something that surprised me was that in the operations, the game runs slightly slower. When you do your first operation, you feel a definite reduction in pace compared to the first - I suffered the indignity of having my first suture counted as a "BAD" before realizing I had to relearn how it was expecting me to do them. Another example is that the syringe seems to have been changed from a smoothly sliding gradient into a series of sprites, giving filling it a much jerkier appearance. It's not unplayably slow - after a while you get used to it and don't notice it at all by itself (indeed, now that I'm at the end of the game and having to touch the screen five times per second it's difficult to imagine how I could ever call the game "slow"), but if you go back to the first game after getting used to this one it's surprising how much faster it seems. I think the screen just doesn't update quite as quickly as before, most noticeably on tools where you have to draw lines like the sutures and scalpel - maybe it was an attempt to combat the slowdown that the first game experienced when there were a lot of objects on the screen at once.

I said before that even though I'm not someone who just skips through cutscenes all the time I didn't really consider the plot of the first game all that important, more a vehicle to trundle the game between operations of increasing unlikeliness and difficulty, but the storyline here has really been brought to the forefront. Rather than just one group fighting a medical terrorist plot, it's been turned into a story about the rivalries between two medical companies and the soap opera of the more personal stories of all of the characters that you meet and work with (while they work tirelessly at pushing your two clueless protagonists into finally going to bed together). I didn't find myself caring all that much about the couple of tragic plot points the first time round, but this one has an absolute heartbreaker that I honestly felt guilty about for most of the day afterwards (made all the worse because in the context of the game I had come nowhere near running out of time - the storyline just dictated that my fastest just wasn't good enough). It seems that even the great Derek Stiles can't compete with storyline injuries.

Perhaps because of the plot taking its time more, the pace of the game seems to sort of dither a bit, and there's more of a concentration on normal-ish operations and upgraded versions of some of the ones that you know and despise from the first game than introducing any completely new ideas. Three of the GUILT strains from the first game return - the classic lung-sharks Kyriaki are back, and they seem to move a bit faster and annoyingly have to be ultrasounded quite precisely before their shadow appears for long enough to start extracting them. As if it wasn't enough trouble before, the large one that always appeared at the end that I called the 'mother' has been replaced with the Queen, which can lay (similarly invisible!) eggs that spawn even more of the things if left alone for too long. Pempti has had a hardware upgrade as it's now dual core, but is actually one of the easiest operations because its attacks have been scaled back to make it remotely fair (it's possible to go through a whole operation without it getting to launch anything now). And I was extremely pleased with the colour-coded Tetarti at first because they'd replaced the colours of "a bit dark", "a bit light" and "blue" with very clear red, blue and yellow - until halfway through the first operation on them, where they had the decency to introduce a purple one. Then a black one as well. With five possible colours, you now have to remember which ones are even present rather than do it by process of elimination, which can make your life difficult very quickly. In addition to this, you're often given some quite creative handicaps, like having to perform an operation with an additional pen-light tool that you need to drag around to see what you're doing at all, or having to perform three operations on one timer, or with limited supplies of certain tools.

The new GUILT strains are almost all confined to the last chapter of the game, which makes it sound like they're underused, but pretty much all of them fall well into the 'boss' category. The beginning of them is wonderfully handled, with Derek in the course of the story being led to believe that he's doing a very normal operation, until a massive green spiny thing bursts out of the patient's small intestine. That serves as your introduction to the new and improved strains.

This is my favourite of the new ones, and it's called Bythos or By-thos or http://www.byethost.com or something. I actually really love this one, as much as you wouldn't expect for something so designed to make your life difficult - it announces itself by popping out of the back of the screen, causing cuts everywhere, and then beginning to bounce around. It's sort of this game's Savato without the annoying bits - while it goes about making various patterns of cuts, you have to zap it with the laser until it falls to bits, and then you have to pick out the core past the blades and glowing spores hovering around in a very sort of Crystal Maze arrangement. After the familiarity of a lot of the game up until then, it's a very original challenge that isn't like anything else either in this game or the first.

Nous is actually the first one you encounter, though you don't know what it is until much later. Until the reintroduction of Tetarti later in the game I thought that this one had been thought up as a harder replacement for it - you have to watch a sequence of tumours generate and then treat them in the same order that they appeared by draining, cutting and excising them, having to remember the positions of up to five in a row, before doing the same procedure to the main body. It's the easiest one provided you can perform the small feat of memory required, but also the most repetitive.

Sige is the third, and it's like Kyriaki on acid - it zooms about making an awful racket and causing all sort of problems until you ultrasound it into visibility, then you have to cut it out and freeze it before attacking it again. The problems that it causes are more varied than Kyriaki, needing draining and scalpelling and injecting as well as suturing, and it's also the only strain to make use of the microphone - you have to physically blow away the clouds of gas that it releases periodically, to clear your view of the operating area. It clones itself a bit later on to make things a bit harder for you, but it's nothing the Healing Touch can't cope with.

Ah, balls.

Until Aletheia, which could best be described as completely bloody impossible. At the start of this operation, you dive down on to the heart to be confronted with a giant eye on its surface blinking up at you, and getting rid of it is a long process - you have to remember how to deal with the variants of the six other strains that it can summon, while stabbing its eyeball with a syringe during any spare moment you find. After you've stuffed it with serum, there's an intermediate stage which is a tense and cruel test of nerves as you have to sever eight strands around it without ever touching the rapidly-changing red one. You have to do this three times and then perform the expected trick to finish it off (which I took a risk on the first time I played it and it ended in catastrophic failure).

But after finally getting past all that, you're triumphantly given a notice that you've now got access to the Confidential Operations, also known as the X-missions. So my descriptions of those are going to have to come much later provided I can complete them at some point within the next hundred years. Thanks a lot, Atlus.

I've just noticed that my DS now has a perfect groove worn into the screen at the point where the stabilizer appears.