The two players alternate turns, each taking one action. The first turn for each player is a little different than the rest, but afterwards, all turns are the same. The Killer always goes first.
First Turn – Killer
On the first turn, the Killer must make a Kill action. To do this, he chooses one of the suspect cards on the board adjacent (either on the sides or the diagonals) to his secret identity, and turns that card face-down, to its deceased side.
First Turn – Inspector
The Inspector must now select one of the 4 cards from his hand to be his secret identity. He sets that card face-down in front of him. He loses if this person is killed. The others he keeps in hand as ‘evidence cards’.
Later Turns – Killer
On each turn, the Killer must choose one of the following 3 actions and perform it.
Shift a row or column
Kill an adjacent suspect
Disguise himself (or attempt to)
Later Turns – Inspector
On each turn, the Inspector must choose one of the following 3 actions and perform it.
Shift a row or column
Arrest an adjacent suspect or yourself
Exonerate a suspect from the deck
Both players have the ability to shift. To do so, select any row or column on the board You do not have to be in it or near the chosen row or column.
Move all cards in the column vertically up or down, or move all cards in the row left or right. This will cause one card to ‘fall off’ the edge of the board. Place the card that falls off onto the new empty space on the other side.
NOTE: You cannot use your shift to ‘undo’ the previous player’s shift. For example, if a player shifts a row right, the next move cannot be to shift that same row left.
The Killer can kill a suspect just like he did on the first turn. He just picks a suspect who is adjacent to his character on the board, and turns that suspect to its deceased side. Since the Inspector is now one of the suspects, if the Inspector is killed, he reveals his identity and the killer wins! Otherwise, play continues.
The Inspector can arrest a suspect whom he is adjacent to on the board. He may even arrest himself to throw off suspicion. He simply points at the suspect and asks the killer “Are you [name]?” If the killer is the named suspect, the Inspector wins! Otherwise, play continues.
The Killer can disguise himself to throw the Inspector off his trail. To do this, he draws a card from the top of the Evidence Deck, and then secretly checks to see if that character is still live on the board.
If it is still alive, he discards his current identity and turns that card to its deceased side, then places the card he drew face-down in front of him. It is his new secret identity.
If the suspect is deceased, he simply discards the card face up, and retains his old identity. His turn is over either way.
The Inspector draws one card from the Evidence Deck into his evidence hand. He must then discard a card from his hand face-up beside the board (if the discarded suspect is still live, it is easier to place the innocent card over top of their suspect card on the board).
After Exonerating, the Inspector’s turn is over, and he should have 3 cards in his evidence hand.
If the Evidence Deck is exhausted, the Disguise and Exonerate actions are no longer available.
If an entire row or column of suspects are deceased, that row or column is removed, and the board shrinks.
If 16 characters are deceased at any time, the game ends and the Killer wins.
In Standard Mode, when you disguise or exonerate, you put the innocent card you discard down onto the board, face-up, covering the existing suspect. If the suspect is already deceased, then don't do this.
If you Exonerate (whether you place the suspect or not), you canvas the area around that suspect for the killer.
If you kill a suspect marked as innocent, you get to canvas the area around that suspect for the inspector.
Citizen's Arrest Mode
In this mode, instead of questioning everyone adjacent to a suspect he exonerates, the Inspector can choose to arrest one adjacent character instead.
Important: This rule applies even when the suspect being exonerated is already dead.
Important: When doing a citizen's arrest, you do not get to draw a new card to replace the exonerated suspect. This permanently reduces the size of the inspector's hand by one. Thus, this option can be exercised at most three times per game.