Yes, it's definitely worth it. The story is full of action and intrigue, set in the rich and complex Warhammer 40K universe. The audiobook version brings the characters and their struggles to life in a vivid way.
I'm not entirely sure which specific 'imperium based on true story' you're referring to. There could be various works with such a title. It might be a book, a movie, or a game. Without more context, it's difficult to say exactly what it's about.
Well, in 'Dark Imperium', the plot is centered on Guilliman coming back. It's a time when the Imperium is in a shambles. There are all kinds of problems. He has to deal with the political mess within the Imperium, where different factions might not be so happy about his return. And on top of that, there are military threats. Alien species are always looking for a chance to attack, and the traitors are still causing trouble. Guilliman has his work cut out for him as he tries to bring back some order and strength to the Imperium.
Guilliman is one of the main characters. He plays a crucial role in trying to save the Imperium. Also, there are other Space Marines and some Imperial officials who are important in the story.
Some libraries also offer digital audiobook services. You could search your local library's digital catalog to see if they have the 'dark imperium novel audiobook'. It might be available for free borrowing if they do.
The novels also focus on the internal struggles within the Imperium. There are power plays, different factions vying for control, and the challenges of maintaining order in a universe filled with chaos. For example, the different Space Marine Chapters may have different views on how to deal with the emerging threats, which causes some tension.