The series tells the origin story of Danny Rand (Jones), the son of a billionaire corporate mogul. The family is involved in a plane crash when Danny is 10, and all of them are presumed dead. Danny mysteriously reappears 15 years later as a super-powered martial artist determined to take down The Hand, the shadowy organization involved in Daredevil. The ties to the other shows are the characters of Claire (played by Rosario Dawson) and Jeri, the lawyer from Jessica Jones (played by Carrie Ann Moss). The story alternates between Danny's reintegration into society and trying to uncover what The Hand is doing in NY. I will not divulge anything else so as not to spoil it, but it packs a lot of story into the 13 episodes.
The show got a lot of bad reviews that, in my opinion, are underserved. The acting is very good, and Finn Jones does a good job with the character Danny Rand. The show is definitely not perfect. One part of the story that I did find a bit ham-fisted was the whole arc with Harold Meachum, but overall I think I think the story of Danny trying to get his life back, reconnect with his childhood friends (played by Jessica Stroup and Tom Pelphrey), as well as trying to take down The Hand was great. The rest of the supporting cast, including Jessica Henwick and David Wenham, did well in their roles. While liking it is, of course, subjective, and for me, it was not as good as Daredevil or Jessica Jones, it was not as bad as many critics made it out to be. I definitely think it is worth taking a chance on.
It does seem there are a couple versions of the Blu-ray set floating around. I have the region-free version with no extras, just the episodes. You can stream it, for now, on Netflix, but given that Netflix canceled it, and all the other Marvel shows, along with losing the rights to the Disney content which will eventually be removed, that may not last. So even if you usually only get the physical discs when there are a lot of extras, this may be worth picking up anyway.