• First Buy-in Bonus
    New customers only. Opt in required. 1 x per customer. Min buy in with £10. Casino tab only. Max £300 bonus. 40x wagering requirement. Max redeemable amount £2,000. Bonus expires 7 days from issue. Eligibility rules, game, location, payment method and currency restrictions, stake contributions and terms and conditions apply.
  • First Buy-in Bonus
    New customers only. Opt in required. 1 x per customer. Min buy in with £10. Casino tab only. Max £300 bonus. 40x wagering requirement. Max redeemable amount £2,000. Bonus expires 7 days from issue. Eligibility rules, game, location, payment method and currency restrictions, stake contributions and terms and conditions apply.
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Game Rules

Sherlock Mystery

5-Reel, 20-Line SlotExtra Wild Multiplier

The main objective of playing Sherlock Mystery online slot is to spin the reels to match winning combinations on the paylines. Sherlock Mystery also boasts a Free Games Bonus and Crime Scene Bonus. Players of online blackjack and poker will be familiar with Ace, King, Queen and Jack Symbols, but the big money payouts are achieved with matching Watson, Holmes and Moriarty Symbols on the paylines!

How to Play:

  • Select the bet per payline by using the +/- buttons underneath the Line Bet Field.
  • Choose paylines by using the +/- buttons underneath the Lines Field. You can also select paylines by choosing a number 1-20 from the sides of the reels. Please note that selecting a number will activate all paylines numerically below it.

Note: The Total Bet = Line Bet x Number of Paylines.

  • Press Spin when you have selected your bets and are ready to play. Select Bet Max if you wish to spin the reels with all 20 paylines activated.
  • Use Auto Play if you wish to play a set number of spins to be played automatically. Pressing Auto Play will allow you to choose between 10, 25, 50 or 99 Auto Spins. When Auto Play Mode is on, the Auto Play button changes to Stop. Press Stop to turn off Auto Play Mode.
  • Click Turbo Mode if you wish to speed up the animations of the reels spinning etc. to achieve faster results.

Note: A winning combination will be clearly highlighted on the reels. The total win for each spin is shown in the Win Field.

Note: All winning combinations and their payouts are shown on the Paytable, which is accessed via the Info button. Line Win payouts are x Line Bet. Scatter Win payouts are x Total Bet.

Info Pages:

You can launch the Sherlock Mystery Info Pages by clicking the Info button on the bottom left of the main screen. Use the arrows on the bottom right of the Info Pages to flip between pages. Press Back to exit and return to the main screen. The Info Pages are as follows:

Paytable – displays all possible payouts for winning combinations.

Crime Scene Bonus – describes the rules and awarding of the Crime Scene Bonus.

Free Games – describes the rules and special features of Free Games.

Paylines – displays the positions of all 20 paylines on the reels.


Paylines are the directions that matching symbols must follow across the reels (left to right) to pay as Line Wins. Only active paylines (the ones that you bet on) can record Line Wins.

Please note the difference between the Line Bet and the Total Bet. The Line Bet is the amount staked on each payline. The Total Bet is the amount staked on all active paylines added together.

About Payouts:

Every possible payout for the main game is listed on the Paytable. A Line Win = Payout x Line Bet. A Scatter Win = Payout x Total Bet.

Only the highest value Line Win will be paid on each individual payline. Multiple Line Wins will be paid if they fall on different paylines. These are added up along (with any Scatter Wins) and paid out as a total win.

A Line Win must start on the first reel, working left to right in a chain of symbols on a payline.

Sherlock Meets Watson:

If the Watson Symbol falls to the immediate right of the Sherlock Symbol on any part of the reels, you will be awarded a payout equal to 3x the Total Bet.

Wild Symbol:

The Wild Symbol (Professor Moriarty) can substitute for all other standard symbols to make the best possible Line Win. Wild Symbols cannot substitute for Scatter and Bonus Symbols.

Wild Symbols can also form their own Line Win with a separate payout.

Note: The Gun Symbol will act as an Extra Wild Symbol during Free Games. This will be explained in a section below.

Scatter Symbol:

The Scatter Symbols (Baker Street Logo) do not need to appear on any paylines to pay out. Three or more Scatter Symbols in any position will award a payout (x Total Bet) and Free Games.

Bonus Symbol:

The Bonus Symbol (Magnifying Glass) appears on Reels 1, 3 and 5 only. It does not have a payout value. Instead, the Crime Scene Bonus will be awarded if three Bonus Symbols appear on these reels simultaneously (in any position).

Crime Scene Bonus:

When awarded, press Click to Start to launch the Crime Scene Bonus. A new screen is launched showing the scene of the crime, which has taken place in a bedroom.

You will be prompted to pick various objects from the crime scene. Hovering over an object with the magnifying glass will light it up. Each object chosen will reveal a cash prize. You can continue to pick objects until picking one reveals Collect. This will end the Crime Scene Bonus.  At that point, all cash prizes that have been revealed will be tallied up and displayed on the results screen.

Press Continue to return to the main game.

Note: The cash prizes awarded in the Crime Scene Bonus are proportional to your Total Bet.

Free Games:

When awarded, press Click to Start to begin the Free Games Bonus. A message appears on screen informing you that you have won 10 Free Games with the Gun Symbol used as an Extra Wild.

The Extra Wild will apply a Random Multiplier (x2, x3, x4 or x5) to any Line Win payout that it substitutes in.

10 Extra Free Games will be awarded if three or more Scatter Symbols fall in any position on the reels.

Please note:

  • Free Games are played automatically. The current remaining Free Games and total win are shown on the top of the screen.
  • Free Games are played with the same active paylines and Line Bet as the triggering spin.
  • It is possible to be awarded the Crime Scene Bonus during Free Games. The total win from the Bonus will be added to the Free Games win.

When all Free Games have been played through, a results screen will appear showing the total win from Free Games and the triggering spin. Press Continue to return to the main game.

Return to Player:

The theoretical RTP (Return to Player) for Sherlock Mystery slot is 94.09%.


The following buttons are used to play Sherlock Mystery slot:

Info – opens the Info Pages, which includes all payout information.

+/- Line Bet – increases/decreases the bet placed on each payline.

+/- Lines – increases/decreases the number of active paylines.

Auto Play – allows you to choose a set number of spins to be played automatically.

Spin – spins the reels at the current bet.

Bet Max – spins the reels with the maximum of 20 paylines activated.

Turbo Mode – speeds up the animations of the reels spinning for faster results.

Casino Toolbar:

The Casino Toolbar runs along the upper and lower edges of the screen. It holds the following tools and displays:

Game Balance – displays your current available balance at the casino.

Cashier – select to launch the main banking tool. You can use the Cashier to deposit and withdraw funds, or to view your transaction history.

Play for Real Money – press to play Sherlock Mystery slot as a real money game at William Hill Casino. This button will only appear when you are playing in Fun Mode.

Menu – click to access the following tools and options:

  • History – view the results of recent spins.
  • Options – adjust settings, including audio and graphics.
  • Help – open this help text.
  • Online Support – contact online customer support.

Close – press this to close the current game and return to the casino lobby.

Quick Deposit – use this tool to deposit funds quickly without opening the Cashier. The Quick Deposit Menu may appear in a pop up window (once only per session) when your balance is running low.

Gadget Bar – when it is enabled, the Gadget Bar will appear on the right-hand side of your screen. It can contain information on online casino bonus offers at William Hill. It can also hold mini casino games, which can be played alongside Sherlock Mystery.

Note on Disconnections:

If you lose internet connection in the middle of a spin in the main game that spin will still be completed. You can view the outcome by accessing History when you reconnect to the internet. If you were using Auto Play, only the next scheduled spin will be completed.

If you lose internet connection when playing the Crime Scene Bonus or Free Games, you will be automatically redirected back to the game when you log into the casino again. All previous wins achieved in the Bonus Features will be awarded, and you can continue playing from where you left off.

Note on Malfunctions:

A game malfunction will void all bets, with the stake returned to the player.