Layton's Mystery Journey: Katrielle and the Millionaires' Conspiracy
Layton's Mystery Journey: Katrielle and the Millionaires' Conspiracy is a 2017 puzzle video game by Level-5. The seventh main entry in the Professor Layton series, it was released for Android, iOS, and the Nintendo 3DS, in 2017, and an enhanced port for the Nintendo Switch in Japan in 2018, and worldwide in 2019. The game centers on Katrielle "Kat" Layton, the daughter of famous archaeologist and puzzle-solver Professor Hershel Layton. With the help of her assistant Ernest Greeves, she solves cases in and around London, alongside a talking dog that, for reasons unknown, only the two of them can understand.
Summary from Wikipedia, available under CC BY-SA, read 5 September 2026.
Your like matters. Every heart nudges this game's GamingPickz Score and where it ranks (a small 5% of the score), so the lists get better for everyone.
- Released
- 2017
- Developer
- Level-5
- Platforms
- 1 systems
- Critics
- Not scored
- Steam Deck
- Unknown
- Download
- Not stated
The record
| First released | 20 July 2017 |
|---|---|
| Developer | Level-5 |
| Publisher | Level-5 |
| Platforms | Nintendo 3DS |
| Genres | Puzzle |
Source. Catalogue facts from Wikidata Q26155339, seeded 30 August 2026.
How long is Layton's Mystery Journey: Katrielle and the Millionaires' Conspiracy? How long to beat it
Total play time for Layton's Mystery Journey: Katrielle and the Millionaires' Conspiracy is about 35.7 hours to do everything, and around 18.7 hours to reach the end of the main story. These are player-submitted times from HowLongToBeat, not our own, shown with the number of players behind each.
| How you play | Hours | Players logged |
|---|---|---|
| Just the main story: straight through the critical path | 18.7h | 66 |
| Main + the extras: story plus the side content most people do | 26.3h | 100 |
| Completionist: everything: 100% the game | 35.7h | 66 |
Source: HowLongToBeat community submissions, read 2026-10-19.
Where Layton's Mystery Journey: Katrielle and the Millionaires' Conspiracy sits on the grid
The grid places every game in the catalogue on measured axes rather than on an opinion. This is where Layton's Mystery Journey: Katrielle and the Millionaires' Conspiracy lands on each map it has the data for, with the share of the catalogue it beats on each axis.
- Year
- 86ahead of 50% of the catalogue
- Reach
- 19ahead of 66% of the catalogue
Percentiles are against the games that carry a reading on that axis, not the whole catalogue: counting a game with no figure as a zero would flatter everything that has one. How the grid works.
What readers say about Layton's Mystery Journey: Katrielle and the Millionaires' Conspiracy
Reviews written by people who have played it. These are separate from the GamingPickz Score and are never averaged into it: that score comes from thousands of Steam reviews with a sample-size correction, and a handful of unverified ratings would distort it rather than improve it.
Loading reviews…
Did it run on your PC?
Tell other players how it ran on your machine. One tap, from your saved PC if you have one.
Where Layton's Mystery Journey: Katrielle and the Millionaires' Conspiracy appears
The ranked lists and finder pages Layton's Mystery Journey: Katrielle and the Millionaires' Conspiracy qualifies for, from its own genre and platform to what it takes to run.
Get the weekly rundown
One email a week: what moved in the rankings, what launched, and what dropped in price. No more than that, and unsubscribing takes one click.
We send the weekly email and nothing else. Your address is never sold, shared or used to build a profile, and it is not readable by anyone visiting this site. See our privacy policy.
Common questions about Layton's Mystery Journey: Katrielle and the Millionaires' Conspiracy
What platforms is Layton's Mystery Journey: Katrielle and the Millionaires' Conspiracy on?
Layton's Mystery Journey: Katrielle and the Millionaires' Conspiracy is available on Nintendo 3DS. It first released in 2017.
Who made Layton's Mystery Journey: Katrielle and the Millionaires' Conspiracy?
Layton's Mystery Journey: Katrielle and the Millionaires' Conspiracy was developed by Level-5 and published by Level-5.
How long does it take to beat Layton's Mystery Journey: Katrielle and the Millionaires' Conspiracy?
about 18.7 hours for the main story, 26.3 hours with the main extras, 35.7 hours to complete everything, from HowLongToBeat's player-submitted times. These are community medians, so your own run may be shorter or longer.