A fantastic Second Doctor story and a very good continuation of the Destiny of the Doctor storyline. Frazer Hines is a much better narrator than Carole Ann Ford and his imitations of Patrick Troughton's Doctor and Zoe are spot on. The story and script here written by Simon Guerrier is very unique and different, with many unexpected twists and turns that take you by surprise, particularly an unexpected cameo (*NO SPOILERS*) that made me smile and seemed like it was meant to be at some point or another (HINT: Bow ties were cool back then as well as now). It definitely feels like a Second Doctor story and would've worked VERY well on screen as well even with some of the modern touches added. A great audio-drama even without the connections to the Destiny of the Doctor story, much better than "Hunters of Earth", and definitely worth multiple listens! Can't wait to see where the story goes from here with Doctor #3!

Secondary characters are a little thin in this one - as of May's release, the second voice is probably utilized least here - but Simon Guerrier's story is a powerhouse of atmosphere, and his crew of the second Doctor, Jamie and Zoe really shine from the first minute on. There's definitely an attempt here to evoke the classic second Doctor stories, but it's not slavishly done; the tone is a little darker and moodier than anything we saw on TV, which in my opinion is all to the good. The minimalist score and excellent scenic descriptions put me strongly in mind of groundbreaking science-fiction movies from the time; there's a definite "2001: A Space Odyssey" quality to it all (I was reminded especially of the sequence with the monolith on the moon), and it even evokes a couple from a few years later, such as "Solaris" and "Silent Running." In the end, the story's wrapped up a little hurriedly, but the journey getting there is so enjoyable I don't mind a bit. This is a keeper.