How can a historical hunt for a missing SS Officer increase museum visits by 30%?

Kamp Amersfoort is not always one of the first Dutch concentration camps that comes to mind, although 47,000 people were imprisoned there. How could we help attract more visitors to the camp? The solution: a rather unique story, belonging to the camp’s founder who mysteriously disappeared: Walter Heinrich.

Telling the story: podcast maker Jordy Hubers and Floris van Dijk, Head of Research at the National Museum Kamp Amersfoort. For eight weeks their informative podcast managed to take hold of the number one spot in Apple Podcast’s history charts. And the camp itself? Kamp Amersfoort saw a 30% increase in visitors.

A podcast serving as the best medium for substantive stories

There is only one medium to tell a story such as this in a substantial way: a podcast. On social media everything has a character maximum, on YouTube you don't really get much time and blogs are often expected to be short and concise.

A podcast is a great medium to tell a substantive, complex story. But in a remarkable place like Kamp Amersfoort, where there are 47,000 stories to tell, of which several are already highlighted in the museum, how do you get all of them into a single series? The answer: you don’t.

We chose to highlight one story. A story not easily found in the museum and one there wasn’t much to share about at the time. Because this podcast turned out to be more than a powerful and suspenseful audio story. It became actual historical research into one of the most important people in the camp: its founder Walter Heinrich.

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Attract (potential) visitors in the museum


An eight-part podcast via fully owned channels

About National Monument Kamp Amersfoort

When you say, ‘Second World War’ and ‘concentration camps in the Netherlands’, many will immediately say Kamp Westerbork or Kamp Vught. But Kamp Amersfoort is not mentioned that often. Yet 47,000 people were imprisoned there, 652 people died and a horrific regime ruled behind its gates.

So, as National Monument Kamp Amersfoort, how do you ensure that visitors find your museum? How can we combine physical and digital experiences and let them enhance each other? How do you tell a substantive story to a wide audience and thereby interest potential visitors?

Listen to the podcast on Spotify:

NOS news broadcast about this podcast

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iO and Nationaal Monument Kamp Amersfoort created an eight-part podcast: The Missing SS Officer. A poignant audio story that has been listened to almost a million times.

“As makers, our starting point was the same as always: we wanted to tell a solid, exciting story. A podcast that combines entertainment and education. With healthy listener numbers, that are already well on the way to reaching the one million mark, we succeeded in introducing a wider audience to the National Monument Kamp Amersfoort.”

Jordy Hubers

Jordy Hubers, Podcast Creative iO

The search for Walter Heinrich

Walter Heinrich was a war criminal, a mass murderer, and the founder of one of the most gruesome concentration camps in the Netherlands during World War II. In February 1945 he disappeared without a trace. What happened to him?

In ‘De Verdwenen SS’er’ (translation: The Missing SS Officer), iO podcast maker Jordy Hubers and Floris van Dijk, Head of Research at National Monument Kamp Amersfoort, went looking for the answer. They investigated all possible leads. Was he killed during the fall of Berlin? Was he a prisoner of war? Did he successfully escape to the other side of the world?

After nine months of research, Jordy and Floris came to surprising discoveries that made national headlines, with a feature on the NOS nightly broadcast news as icing on the cake, bringing the story to 2.4 million viewers. Research carried out during the podcast revealed that Walter Heinrich’s wartime crimes were far worse that had previously been established, and that he was responsible for at least 625 deaths.

The collaboration in numbers




increase in visitors


weeks at #1 in the History category (Apple Podcasts)

Top 10

in the charts (Spotify)


score on average (Apple Podcasts & Spotify)

One of the best branded podcasts in the Netherlands

The podcast was promoted only on owned channels and with free publicity. Thanks to articles and features in the national and regional media, the podcast went viral. With over 850,000 downloads, it made its way to top-ranking positions on both Apple Podcasts and Spotify.

But that's not all. The initial aim was to attract more visitors to National Monument Kamp Amersfoort. And it worked. After the podcast went live in October 2022, the camp saw a visitor increase of 30% compared to the previous month. Where the 'quiet' season traditionally starts from September, in October 2022 there were more visitors than in August.

Whitepaper: Ontdek de kracht van branded podcasts

An award-winning project

In 2023, this project won the following awards:

  • Dutch Creativity Awards

  • Lovie Awards - Gold in category Crime & Justice, Gold in category Documentary, 2x People's Lovie Winner

  • International Content Marketing Awards - 2x Gold in "Branded Podcasts" & "Best Content Campaign", Silver in "Best Content within Media Relations"

  • Esprix Awards - Silver in "Smart Budget" & Bronze in "Charity & Not for Profit"

We couldn't be more proud of this recognition. It's a testament to our intensive collaboration with the client and the right blend of expertise and skills.

“In the end, we put a face and a story to a war criminal who was previously unknown in the Netherlands — filling in some serious gaps in our shared history and knowledge. Along with boosting the museum’s profile and increasing engagement and visitor numbers, I think, even though you have to be careful making statements like this, that ‘The Missing SS Officer’ is the best branded podcast at the moment.”

Jordy Hubers

Jordy Hubers, Podcast Creative iO

Branded podcasts

A strong branded podcast starts with identifying the best stories, coming up with the right format, and choosing the most effective release frequency. iO will guide you through the process.

Podcast opname de verdwenen SS'er
Other podcasts we've created