External Links

Play Online
Play this game in your Web browser.
Complete Collection
This is a pseudo-format used to represent download adviser records that apply to multiple formats.

Have you played this game?

You can rate this game, record that you've played it, or put it on your wish list after you log in.

Playlists and Wishlists

RSS Feeds

New member reviews
Updates to external links
All updates to this page

Fingertips: Who's Knockin' On The Wall?

by Melvin Rangasamy

Episode 27 of Apollo 18 Tribute Album
Logic Puzzle

Web Site

(based on 9 ratings)
2 reviews

About the Story

You live in a vibrant international community, in all senses of the word 'vibrant'. But who is that knocking on the wall?

A completely randomised logic puzzle for Apollo 18+20: The IF Tribute Album.

Game Details


- View the most common tags (What's a tag?)

(Log in to add your own tags)
Tags you added are shown below with checkmarks. To remove one of your tags, simply un-check it.

Enter new tags here (use commas to separate tags):

Member Reviews

5 star:
4 star:
3 star:
2 star:
1 star:
Average Rating:
Number of Reviews: 2
Write a review

2 of 2 people found the following review helpful:
A classic logic puzzle (the kind you solve with a grid), February 14, 2016

This one move game is more puzzly than most games in the Fingertips portion of the Apollo 18 album.

It is a classic logic puzzle, where you are given a dozen or so facts about several people and several properties they have, and you have to deduce who is next to you.

Because I wasn't in the mood for this puzzle, I just guessed, and go it right. Good for fans of such puzzles.

Was this review helpful to you?   Yes   No   Remove vote  
More Options

 | Add a comment 

2 of 2 people found the following review helpful:
A Perfect Logic Puzzle Generator, April 1, 2012
by Joey Jones (UK)

Who's Knockin' is a logic puzzle (or set of possible puzzles) with the same form as the (probably apocryphal) Einstein Puzzle, also known as the Zebra Puzzle. It's a fun and challenging puzzle to solve even if you don't have a degree in predicate logic. The trouble is, if you've solved it once, you always know what the answer is. Not so any more!

If Who's Knockin' merely randomised the names of all elements in the puzzle, then you'd always be able to guess the answer just by looking at the form of the clues: if, for instance, the woodworker is always the person that lives in the second house, you could guess it every time just by looking at the clue saying who lives in the second house. What the game engine does is randomly pick one of five possible puzzle structures (all sharing some identically structured clues), and then it randomises the order in which the clues are listed. This essentially means the game can't be 'gamed', you have to figure it out afresh each time.

While it lacks literary qualities and breadth of response, the game more than achieves what it sets out to achieve: a challenging and unique puzzle with every play. And that's not something many games can boast, let alone one move games.

Was this review helpful to you?   Yes   No   Remove vote  
More Options

 | Add a comment 

Fingertips: Who's Knockin' On The Wall? on IFDB

Recommended Lists

Fingertips: Who's Knockin' On The Wall? appears in the following Recommended Lists:

Apollo 18+20 by Teaspoon
Interactive fiction games, with one game per track on the album Apollo 18 by They Might Be Giants. The regular tracks are generally short games. The Fingertips tracks are one-move games (however the authors interpreted that). The games...

Recommended list by DAB

Little Hidden Gems by Cryptic Puffin
Sometimes it takes a lot of digging to find a nice, chill game to play when you feel like it, and sometimes you end up uncovering some really good, small games that don't really get the attention they deserve. So, here it is, a small...


The following polls include votes for Fingertips: Who's Knockin' On The Wall?:

Nontradiational Parser, Gamebook, IF and Systems by thecanvasrose
I'm making a list based on this poll as I play the elected games and can write snippets about them. See here: https://ifdb.org/viewlist?id=3n6rheokfkcsntf - - - - - - - - - I'm looking for games which are: 》Neither parser nor gamebook...

Games with "logical" puzzles by Victor Gijsbers
Some puzzles--like chess problems or sudokus--can be difficult even though you know all the rules. I'm looking for IF games with this kind of puzzle: you can get to know the rules by simple exploration, and then you still have to solve...

Games with great puzzles by Molly
Games that have great puzzle-design. The puzzles need to be logical and internally consistent.

This is version 5 of this page, edited by Zape on 4 May 2021 at 9:42pm. - View Update History - Edit This Page - Add a News Item - Delete This Page