Originally I did not have a very high opinion of Black Library's audio dramas, seeming to me to be more audio books with a soundtrack, but it looks like one has changed my mind for me. Garro Oath of Moment.

Carrying on from the event of Flight of the Eisenstein, loyalist Death Guard Nathaniel Garro has returned to Terra to bring news of the treachery which has occurred. Now he is without a legion and without  a purpose until Malcador the Sigilite tasks him with gathering together loyal individuals from across the legions to combat the threat of heresy, a mission which leads him to ravaged world of Calth. Here he must find one man of the Ultramarines as they battle against the heretical Word Bearers.

Oath of Moment is possibly the best of the Black Library audio dramas which I have heard. This I think is in no small part due to its subject matter, for here we are seeing the beginnings of the Grey Knights. This helps us to really get a sense of some of the knock on effects the Heresy had on Imperial society, further demonstrated by the way in which the restraints placed upon pskyers as a result of the treachery are shown.

Surprisingly, another area in which this audio drama excels is the area which I have previously criticised Black Library for the most, namely the sound effects. Don't get me wrong, I still think it is more an audio book with bolter blasts fitted in around the narrative rather than a straight up audio drama. However, now I knew what to expect from it I think I was more able to appreciate the way the sound effects can help draw you into the story. For example, the sound of a Defiler crushing a Space Marine's chest will forever be engraved upon my mind. It was awesome.

That's not to say that this story is as good as Horus Rising, in my opinion the best Black Library book written to date.

As an audio drama Oath of Moment is unable to achieve the length needed for a truly in depth story, being 71 minutes in length. But this isn't really much of a problem as it serves to set the stage for the events to come and still manages to cover a good number of issues present within the Horus Heresy.

Another area in which I can find fault is the voice acting. Generally the characters are managed skilfully, with Toby Longworth's narration being truly impressive. On the other hand I cannot help but feel that the voices of some of the characters, particularly Malcador and the Ultramarines leader, come across as somewhat comical.

All in all I would thoroughly recommend this as one of the best audio dramas out there. A brilliant, action packed look at the origins of one of Warhammer 40k's most iconic armies. I cannot wait to get my hands on the sequel Legion of One.