Batman / Nightwing: Bloodborne #1

The virus has no name, but it exists...and it brings death. Now, mere days before it is to be unleashed on the world by a few militant madmen, it strikes a would-be hero - the batman! With the Dark Knight clinging to life in the icy wasteland of rural Russia, only one man can save him. He was raised to be a sidekick. They called him "Robin". Now, Dick Grayson is Nightwing - and he will travel to the ends of the earth to save him mentor and friend. But can he win a race against a biological nightmare and the military extremists who would unleash it on an unsuspecting world?