We know him as Buffy the Vampire Slayer's Spike, the leather coat-wearing badass, but now James Marsters is trading his fangs for a mic and a book.

The 54-year-old actor narrates Cassandra Clare's newest audiobook, Lord of Shadows -- the latest addition to the Shadowhunters canon -- joining a long list of Clare's all-star narrators, including Outlander's Sam Heughan, The 100's Devon Bostick and How to Get Away With Murder's Jack Falahee.

In the exclusive clip above, Marsters gets candid about why he thinks the fantasy genre is important and the real message behind the iconic '90s TV series.

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"One of the things I really like about fantasy is that in fantasy, we can talk more directly about social issues," the Angel star says.

"One of the great things about Buffy was that we weren't just talking about vampires," he notes. "The real thing that we were talking about is woman can defend themselves."

Marsters also discusses the challenges of performing in front of the camera versus voice acting for an audiobook, which reminded him of his stage acting days.

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"The thing about stage is...you're trying to convey the inner workings of the mind to an audience that is half a football field away," he says, adding that the theater trains you to hang words in the air with just the right rhythm and color. "When you’re doing an audiobook, that's exactly what you're doing."

Lord of Shadows is out now!