The Big Lock In & The Mystery of the Missing Castle Rushen Ruby

– Posted on Monday 20th February 2023

Over 400 Brownies, Cubs and their leaders from across the Isle of Man have taken part in the ‘Big Lock In’ at the Manx Museum. Visiting the museum, in the belief they were coming to the Museum to watch a film, their real mission was much more complicated, as they found themselves at the scene of an alleged crime.

After learning that the ‘Castle Rushen Ruby’ had been stolen, the young detectives set to work piecing together evidence hidden in the museum galleries and solving clues to locate the missing treasure.

The children were able to have a go at lifting finger prints, analysing hand writing samples, examining evidence, seeking out secret passageways, DNA swabbing and interviewing suspects. The teams then reported their findings back to the Police in the incident room. After examining the evidence in more detail, and with the help of some incriminating CCTV footage, the culprit was soon apprehended, handcuffed and taken to Douglas Police Station for further questioning.

The ‘The Big Lock In’ was jointly organised by Manx National Heritage and Girlguiding and Scouting Isle of Man to celebrate the 100th anniversary of the Manx Museum.

In addition to the special evening events, a new MUSEUM 100 Guiding & Scouting badge has been launched to encourage young people to explore the heritage and culture of the Isle of Man.

Katie King, Curator: Art and Social History for Manx National Heritage, said:

Manx National Heritage really enjoy working with Girlguiding & Scouting Isle of Man, and were delighted when they agreed to help us celebrate our 100th anniversary through launching a special MUSEUM 100 badge and joining us for ‘The Mystery of the Castle Rushen Ruby’. It was a memorable night for all involved. 

We would like to say a huge thank you to Dean Johnson, and the team at Isle of Man Constabulary, for putting so much effort into the two evenings and for adding realistic quality to the event.  Thanks also to the Manx Museum staff who volunteered their time to become our cast of ‘suspects’ for the night – especially as the Brownies and Cubs treated them all with such suspicion! The young people were fantastic at solving the clues and were excellent detectives”.

Su Simpson, Island Commissioner for Girlguiding Isle of Man, said:

“Girlguiding Isle of Man enjoys working with other organisations, so when we were approached by the Manx Museum to help celebrate their 100th anniversary we embraced the opportunity.

Joining together to produce the MUSEUM 100 badge and challenge pack, along with the ‘Big Lock In’ has been fantastic. We have seen girls from various Units across the Island exploring their Manx roots, Local History, Natural History, Art & Literature, one Unit last week became Vikings for the night. ‘The Big Lock In’ the Brownies and Cubs were amazing solving the clues and finding the thief, they only thought they were there to watch a film. A big thanks goes to all that has been involved from the museum staff to the volunteers from Girlguiding and Scouting Isle of Man”.

For further information on Girl Guiding and Scouting on the Isle of Man, visit and


Media Contact:

Lynsey Clague, Communications Manager

Manx National Heritage

T: 01624 648032


Image: Officers from Isle of Man Constabulary pictured with suspects

Back to top