John Byrne is one of my favourite comic writers and artists. His run on Fantastic Four is to my mind one of the best runs on any superhero comic ever, and made me a fan of the First Family for life. His X-Men, She Hulk, Alpha Flight and Incredible Hulk runs for Marvel, as well as Superman at DC, creator owned Next Men, are all worthy of attention for their concepts, art and quality of story telling.
In his drawn work for IDW on the Star Trek franchise, he created a little bubble of continuity and stories that referenced one another. His Crew followed Number One from the Pike headed Enterprise crew (As seen in The Cage), and Assignment: Earth was intended as an attempt to do the series that the final episode of series two of Star Trek was intended to be a pilot for.
This story is in some ways the third part of this trilogy, which has a certain story line running through it. We see McCoy in a Medecins Sans Frontiers type situation, traveling around in a barely serviceable space ship offering help where needed. The grumpy and yet fundamentally good and wise character DeForest Kelley so masterfully performed is bough back to life, with the voice of the character being captured well.
This being set between the end of the five year mission and Star Trek The Motion Picture, we see a framing device of McCoy relating stories back to Admiral Kirk back at Star Base as he supervises the refit of the Enterprise. We get character development, some very idiomatic Trek style problems to solve, and a couple of warmly welcomed cameo appearances. Well worth a read for any fan of the original series of Star Trek.