The Key game trilogy from Thomas Sing and HABA works a bit differently from other puzzle-based games. You do receive a tiny reward for being the first to come up with a solution, but you might still lose the game to someone who solved the puzzle more efficiently than you did — or just someone who solved the puzzle correctly because you can easily make mistakes when moving in a rush.
In The Key: Murder at the Oakdale Club, you are given a list of three suspects, three murder weapons, three crime scenes, and three getaway vehicles, and you need to figure out which of these items belong to the murder committed at 7:30, which to the 8:00 murder, and which to the 8:15 murder. (Side note: Do not buy a membership at the Oakdale Club.)
The game includes nine cases, each with a different solution, and to play you choose a colored key, which represents a case. Playing simultaneously, you can take as much or as little evidence as you want from the central pile, but only those cards that feature a colored square that matches the key color.
Eyewitness testimony, which has a value of 2, is somewhat helpful, e.g., poison was not the murder weapon at the golf hole or a blonde person was seen on the red golf cart. If you haven't locked in a murder time for the poison, golf hole, red gold cart, or the lone non-blonde, then you can't mark off anything definitive on your private note card — which is akin to a logic puzzle grid, but not as comprehensive — so you'll have to sit on that info for now.
Direct evidence, which has a value of 4, gives you more definitive information, e.g. the murder at 8:15 took place at the club house or Amit Kahn used the golf club in the murder he committed — but the info is often presented in the form of a mini-puzzle, with you needing to match color-coded DNA to one of the suspects or figure out how to read a broken and blood-spattered watch.
All of the cards have icons on the back of them that reveal both their eyewitness/direct evidence status as well as whether the clue on the other side connects the getwaway vehicle and perpetrator, the location and the murder weapon, the time and the perpetrator, and so on. If you've locked in, say, when all three weapons were used in crimes, you can choose not to pick up any more weapon cards to try to avoid getting duplicate evidence or you can dig through the pile for a weapon+perpetrator card since you have nothing locked in for perpetrators yet and want to use what you know as a pillar for everything else. After all, once one detail is locked in, you can often revisit other cards and start filling in the gaps.
As soon as you lock in the times for all three of something, you can consult a chart on your screen to get a number from 1-6 for the order of those items, and once you've locked in each of the four items — suspect, weapon, location, getaway vehicle — for all three times, you'll have a four-digit number that serves as your solution. Once all players have a solution, you confirm the correct answer by placing the color key in a numbered space that matches your solution on a special game board to see whether the key emerges from a field of the same color on the opposite side. If it does, your solution is correct, and of all the people who are correct, the player with the lowest sum of cards looked at wins.
The other two Key cases — Theft at Cliffrock Villa and Sabotage at Lucky Llama Land — have only three elements to organize, not four, so they might be suitable for younger players. Also, they don't involve murder, so that's probably a plus, too.
I've now played The Key: Murder at the Oakdale Club a half-dozen times on a review copy from HABA, and the gameplay flows smoothly after your first game — not that you'll always be correct, mind you. You can easily make false assumptions about something you see, and unless you draw additional evidence cards that cover the same material — which you're trying to avoid doing to keep your evidence total low — you might miss the error because you'll have enough evidence to be certain, but not enough to know that you're wrong. That happens plenty of times in real life, and now you can experience that unpleasantness yourself, but thankfully with far smaller consequences.
In the video below, I show many more examples of evidence cards, explain why a case isn't spoiled despite you having played it, and express wonder at Thomas Sing's versatility given how little this game resembles 2019's The Crew. If anything about the above description seems unclear, watching all the parts in action should help make things clear: