Holmes & the Stolen Stones slot

Holmes & the Stolen Stones slot: the case file

The game puts Sherlock Holmes on the trail of stolen gems in a gaslit London setting. Underneath, it's a five-reel, three-row video slot with 20 fixed paylines, made by Swedish studio Yggdrasil and released in September 2015.

Two things make it worth a closer look. Its 96.8% RTP is above the 96% figure that many games settle on, and it was launched with a set of local jackpots, a feature Yggdrasil promoted heavily at the time. Both affect what you can expect from it, in different ways.

How the Holmes & the Stolen Stones slot machine works

The game follows the standard line-slot pattern. Your total stake is split across 20 lines, the reels stop on positions picked by the random number generator, and any line with three or more matching symbols from the leftmost reel pays according to the paytable. Wilds substitute for regular symbols to complete lines.

1. Set your stake; all 20 lines are always in play.
2. Press spin; the RNG fixes where each reel will stop.
3. The reels take at least 2.5 seconds to settle, under UK rules.
4. Line wins are added up and paid.
5. Random features or the free spins may start, depending on what the RNG has selected.

A 20-line game sits in the middle of the range. With fewer lines than a 243-ways game, individual line wins are clear and easy to follow on screen. Our guide to how slot machines work puts this into the wider picture.

Holmes & the Stolen Stones features and free spins

Yggdrasil built the game around several base-game features that can start at random on a spin, plus a free spins round reached through bonus symbols. Random features like these give a spin a second chance to pay: for example by adding wilds or changing symbols after the reels stop. They're chosen by the RNG on that spin and are part of the 96.8% return, not an extra.

Each feature is described in the in-game rules, along with the number of bonus symbols that start the free spins, how many spins are given and what changes during the round. We don't repeat specific values here because they aren't in the sources we can verify, and old summaries of a 2015 game may not match the version now supplied to Great Britain.

Because features add value on some spins and nothing on most, a feature-heavy game spreads its return across more kinds of event. That's part of why the medium volatility rating fits: wins come from several sources rather than one big bonus.

The local jackpots: how they work

When the game launched, a 2015 industry report described it as carrying five local progressive jackpots, with prizes that it said ranged from €40 to €10,000 and were won several times a month. 'Local' means the pots are shared only within one operator, or a group of its brands, rather than across many casinos. The report also said operators could choose how to pool them.

A local progressive jackpot is funded by a small slice of every eligible stake. That slice comes out of the RTP, so the more of the return set aside for jackpots, the less is left for ordinary wins. Whether a particular UK casino runs the jackpots, and at what values, depends on its version; the jackpot meters on screen and the help screen are the place to check.

For more on how these pots grow and get paid, see how jackpots are funded.

Holmes & the Stolen Stones RTP: what 96.8% is worth

An RTP of 96.8% means the game keeps 3.2% of stakes over the long run. That's 0.8 percentage points better than a 96% game and well ahead of slots set at 94%. Over a short session the difference is invisible; over a lot of play it's real money.

So at £1 a spin, every 100 spins costs about 80p less on average than a 96% game and £2.80 less than a 94% game. That's why we suggest checking the help screen: casinos can sometimes choose lower RTP settings for a game, and the figure displayed is the one that applies. Our list of high RTP slot machines and the page on whether high RTP slots are better explain the limits of RTP as a guide.

Volatility and session shape

Medium volatility means wins arrive at a moderate rate and in moderate sizes. Compared with a high-volatility game, you'll usually see the balance rise and fall in smaller steps, and a budget tends to last more spins. You can still have long runs without a feature, and the RTP still means the average result is a loss.

As an illustration: with £30 at 30p a spin you have 100 spins. The long-run average cost is 96p. In practice, many sessions will end somewhere between £15 and £40 and a few far outside that range; those numbers are an illustration, not a prediction.

Max win and stake limits on Holmes & the Stolen Stones

We don't publish a max win for this game because there isn't one in the sources we can verify. Check the developer's figure in the rules for the version in front of you, and any jackpot meters show their current values. Read the casino's terms for any single-payout limit too; our page on max win caps explains how they work.

The stake you can choose is limited by law. Since 9 April 2025 the maximum is £5 a spin for players aged 25 and over, and since 21 May 2025 it's £2 for players aged 18 to 24, as set out in the Gambling Commission's stake limit guidance (opens in a new tab).

Why the UK version may look different from 2015

This game is older than the UK's game-design rules, so versions offered in Great Britain have been changed to follow them. Since 31 October 2021 slots here can't offer autoplay, must take at least 2.5 seconds per spin, can't use turbo or slam-stop, and mustn't celebrate returns that are equal to or less than the stake. The Commission's online games design consultation response (opens in a new tab) explains the reasoning.

There's a plain-English summary of all of these on our slot game design rules page.

Trying the free demo first

Free demo play, after age verification, is available at UK-licensed sites that carry the game; the Commission's age and ID verification guide (opens in a new tab) explains why you're asked to verify first. A demo is a sensible way to see the random features and the free spins in action. It won't show local jackpot pots growing, and a short demo says nothing reliable about your next real session. Our demo slots guide explains more.

Other Yggdrasil slots to compare

Yggdrasil's catalogue on our site runs from steady to spiky. Here are four with published figures, so you can compare like with like.

Read more on Vikings Go Wild, Jackpot Raiders and Valley of the Gods.

Is Holmes & the Stolen Stones worth playing?

For a player who values a higher RTP and a steadier pace over headline multipliers, it's a reasonable choice. Like every slot, it's paid entertainment; see our guide to choosing a slot machine for other factors.

Detective work: myths that don't hold up

• 'A jackpot that hasn't paid for a while is due.' Local jackpots still pay at random; a big pot isn't a sign it's close.
• 'High RTP means I'll win.' It means a lower average cost, not a profit.
• 'Spotting a pattern in the features helps.' Features are random each spin. See do slot machines have patterns.

Where to play Holmes & the Stolen Stones in the UK

We promote five UK-licensed casinos and can't say whether any of them lists this game today: search the casino's lobby, because game availability changes. New Coral players who bet £10 on slots get 100 free spins at 10p each on selected games; Ladbrokes gives 50 free spins a day for 10 days (up to 500, 10p each) after £10 of slot play; PlayOJO's 80 no-wagering spins on a £10 first deposit are played on Big Bass Bonanza. All are 18+ and terms apply. Read more on our casinos page and browse the slots hub.

If you want to stop gambling online for a while, GAMSTOP (opens in a new tab) blocks access to every UK-licensed site for the period you choose.

18+. Gambling should be entertainment that costs money, not a way to make it. Decide a budget before you play: plan a slot budget. Free, confidential help: National Gambling Helpline 0808 8020 133.