The Professor Layton series was an endearing part of the DS and 3DS generation, spawning six main-series titles and a spin-off with Ace Attorney. After that point Level-5 called it a day on the puzzle solving gentleman, no doubt concerned about the IP losing its freshness and a general decline in sales. It was a sad moment, though, considering how fond many had become not only of the cast of characters, but the entire premise of the IP.

There have been spin-offs and mobile releases since, but now we have Layton's Mystery Journey: Katrielle and the Millionaires' Conspiracy. It arrived on mobile earlier in the year but now finds a home on 3DS, and in various ways it's a series rebirth; for every minor diversion it takes from the original games there are half a dozen familiar features. Level-5 has indeed shaken up the puzzle a little, but the solution remains very familiar.

The main puzzle solver extraordinaire this time is Katrielle Layton, apparent daughter of the Professor and the new head of her very own Detective Agency. She's joined by her assistant Ernest - the game is big on names riffing on characteristics - and a talking dog called Sherl with no memory. So yeah, it's quirky.

The notable formulaic shift is that the story isn't told through a cohesive linear narrative, but through a number of separate 'cases' to solve. You play through these like you would previous series entries, but the change is that you gradually uncover six clues to 'solve' each case before you then move on to the next. There are some story hooks that hang together through the whole thing, revolving around our sleuths and a group of millionaires (called Dragons, someone at Level-5 has been watching British TV) that are at the core of most of the cases.

It's a nice little spin, though unlike the later entries of the main series the diverse nature of tackling the cases doesn't lead to a globetrotting adventure. It all happens in London, or rather a whimsical tea-and-cucumber-sandwiches version of it, with multiple visits to some areas. That's not to say you don't see a variety of settings, but it's all rooted in a very charming and idealistic take on 'old England', where most gentleman and gentlewomen wear hats and sound like the cast of Oliver. 

Beyond the 'case' structure, those familiar with previous main series entries will feel right at home with the mechanics. You investigate areas with a magnifying glass, tapping on points of interest to find Hint Coins, clues and puzzles. You chat to the locals - which comprises of a relatively small cast all told - to engage in light-hearted conversation, gain leads and, yes, unlock more puzzles. It's all rather delightful, and you'll be pleased to know the Level-5's writers and localisation teams haven't lost their touch; it's a game that raises many smiles through its dialogue and story events.

If anything, the formula is too familiar - the idea of solving 'cases' is nice in principle, and you can try and figure each out as you learn more, but the hook is the same as when the Professor solved mysteries. You don't really piece the clues together, they just appear as you play in typical Layton style - the 'detective' angle could have been taken a little further by Level-5, we'd suggest.

That said, this game continues to do what it's predecessors did, which is marry appealing storytelling and witty writing with a lot of puzzles. It's always been an enticing combination, and by closely following the lead of its predecessors Layton's Mystery Journey shares the same strengths. There are a staggering number of puzzles to find, and typically a playthrough of a case can leave some undiscovered, encouraging you to go back and track them down. There are more puzzles even than in the originals, with more promised as regular download extras. 

For the most part they're accomplished efforts, too, though like all games in the series there are a few duds. The majority are excellent, not only for the clever solutions but in the way they encourage you to think outside the box - sometimes the puzzle will throw up red herrings to make you miss a simple solution, leading to the familiar doubts as you submit your answer. There are maybe a few too many puzzles that can be solved through sheer bloody minded persistence rather than deduction, but overall it's an enjoyable collection.

Also, and in keeping with the 'back to Plan A' approach here, there are fun little minigames and extras that you gradually unlock in your suitcase. From picking out the right meals for restaurant guests, to basic retail management and helping Sherl 'escape' the dog pound, they're nice little diversions. You can also recap on key points of cases, view extra cutscenes to fill in small gaps in the story, change Katrielle's clothes of even refurbish the office.

So we have lots of puzzles and whimsical storytelling - with a Layton-esque twist at the end. What's not to like? Well, for one thing, Level-5 took a step back in not bothering to utilise the 3D capability of the top screen. Rather like with another current title - Mario & Luigi: Superstar Saga + Bowser's Minions - this just seems like a cost-cutting or lazy measure. Not a dealbreaker, of course, but it's a shame that a unique selling point of the hardware is being let go late in its lifecycle.

Aside from that there's little to complain about here, apart from the aforementioned cautious approach from Level-5. It could have taken the detective work further while retaining the IP's core gameplay, but instead it feels a little tacked on. Because of that, and the more limited scope of the London setting, the story doesn't quite hit the heights of the finest Professor tales, even in his earliest days exploring a mysterious village. It's still all jolly nice, however, and the new cast are easy to like; there's potential for a series rebirth to live beyond this entry.

Conclusion

Layton's Mystery Journey: Katrielle and the Millionaire's Conspiracy feels rather comforting, the video game equivalent of a warm blanket. For the most part it reverts to the core formula of the Professor Layton games, albeit with a new cast and by dividing the narrative into mostly lighthearted, charming 'cases'. All it lacks is the confidence to fully embrace its new setting, stopping short of expanding upon some of its ideas.

That said, it still delivers the series' unique blend of storytelling and lots of puzzles with aplomb. It'll have fans and newcomers scratching their heads and smiling at the same time; here's hoping it's not Layton's final mystery.