Navigating the landscape of serialized podcasts
My colleague Miriam and I are currently working on a marketing campaign for a soon-to-be released podcast. I can’t share many details just yet, but I can tell you the show will be a limited-run investigative documentary series.
In Apple’s parlance, it’s a “serial” show:
Serial shows are designed to be listened to in sequential order — from the first episode to the last. These include documentaries, investigative reports, scripted dramas, and fictionalized narratives. When you set your show type to serial, episodes are presented in sequential order with the first episode at the top of the show page and the final episode at the bottom.
Spotify’s system offers a similar mechanism for ordering episodes, with different “consumption order” options that impact how episodes are ordered and displayed: episodic, sequential, and recent.
Different consumption patterns
Here at Bumper, we’ve seen first-hand how the consumption patterns of serialized shows differ from those of so-called “episodic” shows.
For example, given how serialized shows are presented to listeners, earlier episodes typically have more verified listeners than later episodes. Conversely, episode retention and average listen time are almost always higher for later episodes compared to earlier episodes. Why? Because not everyone who starts a serialized show makes it to the final episode (see also survivorship bias). Early episodes — especially the first episode in a narrative series — will have the greatest percentage of tire-kickers who bail on the series and won’t return for later episodes.
We’ve also learned that successfully marketing a limited-run serialized show demands a different approach than marketing always-on, episodic shows. And one of the most important considerations is who you market a serialized show to.
Fish where the fish are
There’s a reason so many true crime podcasters market their shows on other true crime podcasts, and why so many fiction podcasters cross-promote their shows with other fiction podcasters. It works. Existing genre affinity and the limited-run nature of these types of shows can be a powerful combination.
According to 2024 research from Sounds Profitable, 74% of US podcast consumers who listened to a limited series in the last year went on to look for another podcast to listen to.
Given this, it makes a lot of sense for Radioactive: The Karen Silkwood Mystery (ABC News) to drop a full episode of their show down the feed of Chameleon (Sony Music Entertainment / Campside Media), as they did in November 2024.
Importantly, Chameleon shared the first episode of Radioactive with their listeners. The episode raises a number of questions, and teases answers at the end of the episode. From the transcript:
By the time Steve, Drew and Burnham arrived at the scene of Karen’s crash, just about every trace of her had vanished. Everything except that paycheck in the mud. Karen, gone. The car, gone. And crucially, those documents, the one she was supposed to deliver to Steve and Burnham, gone.
What exactly was Karen uncovering about Kermagee? What secrets could those documents have held? That’s next time…
The narrative style of the show lends itself to this kind of pitch forward, and for the right Chameleon listener who chose to hit play on this feed drop, this tease might be enough to convince them to seek out the next episode of Radioactive.
But in order for this to work, there needs to be meaningful audience overlap between the two shows. If we want to fish where the fish are, we need to answer an important question…
Where are the fish?
Here at Bumper, we use podcast neighbourhoods to understand audience affinities among podcast listeners. Podcast neighbourhoods are a way to apply network graph analysis techniques to real-world podcast consumption data so we can better understand audience cohorts.
In these maps, each podcast is represented by a circle. The lines that connect them represent common audiences. By studying this pattern of connections between shows, we can identify clusters of shows with strong audience overlap.
For example, a podcast neighbourhood map of the top shows in the Apple Podcasts US Mental Health category reveals distinct clusters of shows and audiences interested in meditation, ADHD, sleep, addiction and recovery, narcissism, and more:
Podcast neighbourhoods can be used to map categories of shows, or search keywords, or the neighbours surrounding a specific show.
But how might we identify audiences that are into serialized shows?
The serialized podcast neighbourhood
In October 2024, Apple announced a new Top Series Chart to spotlight serialized shows. Apple offers this chart in many different territories around the world. As soon as I saw the announcement about these charts, I suspected we could use them to build podcast neighbourhood maps.
And indeed, we can. Here’s a map of the 100 Top Series in Apple Podcasts US, as of early January 2024:
A quick glance at this neighbourhood maps reveals a few things:
A lot of true crime. Though Apple’s Top Series chart aggregates shows across all of Apple’s categories, true crime is extremely well-represented in the top 100. While other genres (e.g. fiction, history, business) do appear on Apple’s Top Series chart, it’s worth noting just how prevalent true crime is. If you publish a serialized show that isn’t true crime, it’s worth calibrating your expectations about appearing on this list.
Strong interconnectedness. Each straight line on the map represents audience overlap between two shows. The density of connections here is striking.
The strength of “omnibus” shows. On this map, the size of each show’s circle represents the number of connections a show has to other shows on the map. The two most-connected shows on the map are The Binge Cases: Scary Terri and The Binge Crimes: Deadly Fortune. Both shows are part of The Binge from Sony Music Entertainment, and both shows are based on multi-season “omnibus” feeds. Scary Terri is season 12, which took over from Denise Didn’t Come Home (season 11), which took over from The Greatest Scam Ever Written (season 10), and so on. Releasing multiple seasons/shows in the same feed offers several benefits. It increases predictability of monetizable ad inventory, and avoids the challenge of starting from scratch with a new feed. But it also takes advantage of the fact that Apple’s Top Series chart uses the show as its atomic unit. A show like The Binge Cases containing 12 distinct serialized stories (one per season) is treated as a single show by Apple, which means listener and follower counts are accrued by a single show.
If you’re marketing a serialized show, it makes sense to try and reach people who already listen to serialized shows. Fish where the fish are.
But what about people who don’t yet identify as fans of serialized shows? Audiences who might be open to a serialized show, but haven’t tried one yet, or haven’t tried one in a while?
One step farther: serialized podcast onramps
One helpful feature of Bumper’s podcast neighbourhood tool is that we can take a list of shows, like the 100 shows on Apple’s Top Series chart, and extend it by one degree. This lets us answer the question, “Which shows do people who listen to popular serialized shows also listen to?”
Or to put it another way, “What non-serialized shows do listeners of popular serialized shows also listen to?” This can be a data-informed way to identify opportunities for feed drops, promo swaps, and guest appearances.
I took the 100 shows on Apple’s Top Series chart, and for each show, got a list of the shows their listeners also follow. The result is a map that includes 668 shows (305 serial, 363 episodic). All of the shows on the map are within one degree of connection to a popular serialized show:
And we can even break out shows based on their type: serial or episodic. For instance, here are the episodic shows that are within one degree of connection to a popular serialized show:
The shows on this expanded map represent opportunities to reach listeners of episodic shows that could be convinced to sample a serialized show.
Remember
Consumption patterns for serialized shows often differ greatly from episodic shows
Apple introduced a Top Series chart in October 2024 that lists the 100 top serialized shows
Apple’s Top Series chart is dominated by true crime programming. Shows on Apple’s Top Series chart have a high degree of connectedness, suggesting strong audience overlap among serialized podcast fans.
If you’re marketing a serialized podcast, start by trying to reach audiences that already have experience with serialized podcasts. Then, expand beyond these existing fans by looking at the extended neighbourhood surrounding top serialized shows.