Another angle: sometimes "killer" in titles is used metaphorically, like "Killer Book" meaning a very good one. Could it be a collection of photos or works labeled as "Killer" that Gabriel and Daniel contributed to?
If the user is looking for photos related to their work on anti-fascist movements, which could be considered "killer" in terms of impact, that's possible. Alternatively, they might be referring to "killer photos" as in impactful images from their campaigns.
In summary, the user is likely seeking information about the collaborative work between Gabriel Kuhn and Daniel Perry related to "Killer" photos, possibly from anti-fascist or activist projects. They need a detailed guide on this topic, which might include their contributions, the context of their work, and resources where to find the photos.