RIP. He was a great actor. Firefly is one of my favorite shows of all time, and Shepherd Book was such a memorable character thanks to his performance. He wasn't in Serenity much, but his part was hugely impactful to the plot and the character development of Mal. I also highly enjoyed seeing him pop up on Agents of SHIELD.
Its sad to hear this. I've only ever seen him in Agents of SHIELD and Firefly. I wish we could have gotten him back for one more episode. I guess we won't be seeing his character anymore.
