
Danger in the Deep is a collaborative escape-room-style game from Professor Puzzle. Trapped on a submarine, you’ve got two hours to track down a spy and stop them from launching the boat’s nuclear warheads. With plenty of obstacles (puzzles) along the way, can you beat the clock and prevent disaster?
Players: 1-6 // Age: 14+ // Playtime: 2 hours
What you need: A pen/pencil and a pair of scissors.
This is a one-time experience with some components destroyed or manipulated during gameplay.
First impressions
When a friend announces that they have a rare childless evening and want to spend it with you, it’s a big responsibility to make it count. Having talked for far too long about getting together to play some escape games, now was the time to make it happen. I suggested a trip to the Thirsty Meeples board game cafe in Bath, followed by a meal at one of our favourite restaurants. We arrived at the cafe with a copy of Danger in the Deep in hand and the main objective of averting a nuclear catastrophe in under two hours.
The game is designed for 1-6 players, but our team of three felt like the perfect number. The time estimate of 2 hours was pretty accurate – we came in close to this, but would have finished faster if it wasn’t for a slip-up early on.
When trying to select an appropriate game, I realised that I don’t own many entirely analogue experiences. While I love games that fuse online and offline gameplay, they are a little trickier to enjoy in a cafe setting. The fact that Danger in the Deep is entirely offline made it the perfect choice on this occasion.
Synopsis
“It’s another day, another mission and another chance for you to save the world in this immersive escape room game from Professor Puzzle.
As a world-class secret agent, you’ve had your share of dangerous missions, but none quite like this. On board the deserted submarine Retiarius, your assignment to track down an enemy agent spirals out of control when you discover the vessel’s warheads are primed to launch! Using all your secret agent training, you need to navigate your way through the engine room, crew’s quarters, mess and control room of the sub.”
Presentation
The distinctive box art features the Retiarius submarine, which acts as the ‘prison’ for the player. Something about the colour palette and style gives off an air of espionage. The box also has a neat red plastic window that allows you a glimpse of the contents. I’m surprised that this is the first tabletop escape game I’ve played with this setting, as its isolated nature is perfect for ‘locked in’ experiences.

Inside, you’ll find a whole bunch of components, including training manuals, a chunky UV torch and a ‘secret box’ that remains closed for the start of the game. One of my favourite components is the beautiful A3 blueprint of the submarine. This is a great example of an item that thematically makes sense and naturally weaves into multiple puzzles. The box is also fully utilised during gameplay in fun and interesting ways. Overall, everything is well-themed and cohesive, with a great colour palette running throughout.
Gameplay
Getting started
You’ll start with a booklet labelled ‘Read First’. This includes a mission briefing and instructions on how gameplay works. A card-based system is used in this game that will be familiar to some. You place a stack of numbered cards face down on the table and only draw them when instructed. You’ll be told which card to start with, and the next won’t be unlocked until you have correctly solved the puzzle.
There was some initial confusion when we began playing, as the how-to guide instructed us to leave everything except the puzzle cards in the box. We then waited to be told when we could start using the box contents, but it became clear that we could access most items as soon as the game began.

Danger in the Deep has been built on the idea that the game is timed, which ramps up the pressure and heightens immersion. We did feel a sense of urgency while playing, which some more competitive players may enjoy. That being said, you could easily play the game without a timer if you prefer.
Aside from a pair of scissors, everything you need to play this game is in the box. No outside knowledge is required, so you won’t need to be reaching for Google. One example is a ‘Learn how to decode Morse code’ guide that’s found in one of the training manuals.
Puzzles
We were impressed with the range of puzzles, some of which required combining items in interesting and unexpected ways. You can expect puzzles to include logic, elimination, flashing a UV torch over everything and some outside-the-box thinking. The signposting is generally really good and I particularly liked a rather clever use of semaphore in one of the puzzles!

One thing I would highlight is to ensure that you don’t disregard an item once you’ve used it. You may find that some items you have already used come into play again. If you find yourself stuck, make sure to look through everything in the box again before reaching for the hints. The chances are, you may have overlooked a hidden detail or skipped over something in a document you’ve already read.
You can verify your answers on the Answer verification page in the ‘Read First’ booklet; this uses a scratch-card-style system. Simply scratch off the box underneath the chosen answer symbol. If correct, you will find a green card with a number that indicates which card/s you need to select next. Reveal a red card underneath and you’ll have to go back to the puzzle and try again.
This is a collaborative experience that allows each player to have their moment to shine. One of the things I love most about escape games is the mix of puzzle types to suit a range of players. All in all, everyone played a fairly equal part in the success on this occasion, and the crisis was averted!
Hints & Difficulty
The difficulty was set at a fairly standard level, with some easier and trickier puzzles in the mix. Our initial stumbling block with misinterpreting the instructions led us to a rockier start than we would have hoped for, but we found our footing fairly quickly.
Hints are available in the ‘Read first’ booklet, using the same scratch-card format as the Answer verification page. Each puzzle includes two scratchable hints and a solution.
Verdict

Danger in the Deep
Summary
Danger in the Deep throws players into the deep end of an espionage thriller, where they are the main protagonist. It’s two-hour countdown ramps up the tension as you race to stop a nuclear disaster, one puzzle at a time. While fairly light on narrative, we were still absorbed into the world and found that the time flew by as we worked together to find answers.
The analogue nature of the game means you aren’t shackled to a laptop or a phone and can play anywhere. Collaborative gameplay makes this escape-room-style game fun for multiple players, although it can also be enjoyed solo. Overall, a solid offering from Professor Puzzle!
About Professor Puzzle

Professor Puzzle creates a wide range of puzzles, board games and outdoor games. They have released many escape-room-style games over the years, with one of my personal favourites being Curse of the Dark.
Disclaimer: Professor Puzzle kindly sent me a copy of this game in exchange for an honest review. This in no way influences the content of my review.
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