It isn’t every adventure game that can make you chuckle from its start menu alone. Yet from the outset Detective Case and Clown Bot in The Express Killer, with its surreal instruction to “kiss the keyboard”, raises a smile. As the titular P.I. and his robot buddy progress through a comic cartoon tale of body bags, bongos and many, many teeth (I cannot stress enough the amount of teeth), this continual eagerness to be abstract and wacky starts to grate. Unfortunately, this and some issues with dialogue and pixel hunting mean that Nerd Monkeys’s inventive style of play just isn’t enough to stop this sequel from jumping the tracks.

This isn’t the first title featuring our dynamic duo, but having not played Murder in the Hotel Lisbon myself, there was very little in The Express Killer that didn’t make sense, save the odd in-joke. Detective Justin Case, who like any good detective starts this adventure by waking up in a foggy haze of alcoholic regrets, has just recovered from a questionable night out on the town when he and his hovering mechanical sidekick Clown Bot are assigned to an intriguing case on that most exotic of all public transport – a train.

A killer is loose on the express route from Lisbon to Porto: passengers are being very violently terminated and it’s up to Case and Clown Bot to hop on the train to find the culprit and (loco)motive. Thus starts an enjoyably farcical quest, at least at first, as the pair race to interview every passenger and potential suspect on board, whilst all around them more and more commuters get bumped off with alarming and darkly hilarious regularity.

The game is divided into several acts, the majority of which are spent on the train, which is itself split into three carriages to explore. It may sound as if there’d be very little to discover after a few minutes of car-hopping, but nearly every inch of screen in this adventure hides an item to be clicked on or collected, and it wasn’t until near the very end that I found myself tired of trundling through the same three rooms. Interaction happens through a verb coin interface; a left-click brings up icons such as a mouth to talk to someone or a hand to use an item, and Clown Bot acts as your floating inventory. However, puzzles in the main section aboard the express are largely made up of locating the correct objects hidden around the train and then notifying passengers when you have them, rather than any challenge in combining them or even using them, which is half the fun in most other adventure games.

And then there are the teeth. With a bit of persistence, most of the items that need to be found can be discovered fairly easily, but one challenge asks you to find 29 teeth – visualized as 29 tiny white pixels hidden amongst the train carriages. It’s most appropriate that this task felt like pulling teeth – I ended up finding the majority of choppers whilst taking part in other challenges, but the search for the last few became a very frustrating and boring game of pixel hunting. Some I just couldn’t find at all despite combing the screen several times with the cursor, which highlights items when hovering over them to make them very slightly easier to see. I eventually and somewhat reluctantly turned to a guide to find the final few. After discovering the locations I was glad I did, as without dragging my mouse over every inch of the screen they would have been impossible to spot, especially as the pixels for the particularly difficult ones aren’t even white. It feels like the developers added the teeth problem to make up for a lack of complexity elsewhere, but it would have been better for everyone’s sanity to not have as many, or at least keep it as a completionist’s target rather than one of the main goals of the game.

Along with the item gathering there are also some inventive mini-games scattered like so many body bags throughout the story. Whether it’s having to correctly fit those 29 newly-found rotten and infected teeth back into their rightful denture sockets (complete with gungy gum sound effects) or remember the correct pattern played by a stereotypical bongo-playing Jamaican whilst inhaling questionable substances from a pipe, these games are enjoyable and help to break up the story, and I would have preferred more of them than the scavenger hunting.

Once the requirements for each passenger / suspect are completed and all objects relating to them found, Case and Clown Bot get the chance to interview them. This comes in the form of another mini-game which those who have played Murder in the Hotel Lisbon will recognize. You must decide whether to have the Detective or CB conduct the interview, and then in a simplified interrogation à la L.A. Noire, choose the correct question out of a selection of three and the inventory item that backs up your line of questioning to “crack” the suspect and find out whether they’re hiding anything.

Unfortunately, the questions themselves make little sense. Each round you get correct, the music becomes more and more frantic and the gestures of the suspects become noticeably more exaggerated and outlandish, but there’s little logical explanation as to why your questions are causing this effect. Why is a banker getting worried about his fake moustaches left behind in a different carriage being discovered – and why would that mean he might be the murderer? Like much of the other components of the game, the idea behind the interview stage is entertaining and it’s admirable to see an adventure game willing to keep throwing different formats and ideas at the player, but the execution just isn’t quite up to scratch.

General dialogue between Case, CB and their fellow passengers suffers the same fate. There’s the occasional funny joke, particularly of the meta variety – e.g. Case asking what’s wrong with a character and CB explaining that his animators aren’t finished with him yet so he can’t reply. But some rushed English translation from the original Portuguese means that occasionally a word is spelt wrong, or that a non-English word (e.g. “mas”) is slipped into the translation by accident. It’s not a huge issue in the grand scheme of things, but it does serve to detract from the immersion the game is trying to create.

Nerd Monkeys are obviously fans of breaking the fourth wall, as every five minutes when something significant or supposedly funny happens, a silhouetted audience pops up to hoot, jeer or laugh, perhaps to excuse the real audience not doing so. This really gets quite tiring after a while, and I searched in vain for an option in the settings to turn this off. Similarly, the joke that Case can’t remember anybody’s name isn’t particularly amusing to start with and only gets more annoying the tenth or eleventh time it’s repeated. Humour may be subjective, but there’s very few who will find themselves chuckling out loud as the Detective once again slips up with a name – unless they’re a member of the lively on-screen audience who can’t seem to get enough of it.

But you have to hand it to the indie development team for their persistence in trying to make you laugh. Perhaps one of the best gags of the game is a visual and audio one. Passing from the economy train carriages to first class, the view suddenly turns from depicting grotty, falling-apart seats and cracked windows to grand chandeliers swinging from the ceiling, champagne and a billiards table, whilst the soundtrack switches from looping piano to Petzold’s prim and proper “Minuet in G Major”. In general, The Express Killer’s pixel art calls back another game starring a befuddled detective and non-human sidekick duo, Sam & Max Hit The Road, though less pixelated with slightly cleaner definitions. Having so few scenes and most of those consisting of train carriages means that there’s not as much in the way of detail – a few more extra things to see akin to the first class joke wouldn’t have gone amiss.

All dialogue is written, with no voice-over, so sound is mainly in the form of the repeating score which changes slightly depending on the location or situation, as well as a few sound effects (gungy teeth!). Click on a street band busking at the train station, however, and you’ll be treated to a rousing rock number. The usual short tracks of jazzy flutes and keyboard chords are catchy enough and fairly innocuous sounding, so whilst not particularly memorable, they do serve their basic function without grating on you as they’re played again and again.

The game is relatively short, taking roughly 4-6 hours to finish, depending on whether you choose to complete the optional side quests, and of course on how long it takes you to hunt down those elusive teeth. Without giving too much away, the final reveal of the mysterious killer is fitting for the surreal story and surprisingly one of the strongest parts of the whole plot – it’s fairly unlikely you’ll be able to guess whodunit without a bit of abstract thinking.

If you’re willing to look past some of the annoying issues in Detective Case and Clown Bot in The Express Killer – the occasionally confusing dialogue, laborious pixel hunting and slightly limited puzzles – then there is a somewhat fun game to be enjoyed here. Nerd Monkeys clearly love adventure games and their enthusiasm for the genre can at times be infectious, making you hope for more amusing mini-games or unexpected twists in the bonkers plot. It’s a shame, then, that such moments are all too rare, and what you’re left with instead is a game that grinds to a halt whenever it’s about to pick up momentum.