I got through the whole 3rd series of Blake's 7 and found it a slight bit better than the previous two series but that's because Gareth Thomas left the series. He was pretty awful as a character. It's still got all the problems that the other two series have, bad stories, dialog, sets, effects and props. Some of the plot devices are pretty stupid and the characters continually make the stupid decisions. It's a frustrating show at times. I think I'm only watching it so I can complain about it. Gotta have some fun and it's a show that needs a good walloping once in a while.
The title character Roj Blake goes missing along with the blond lady from the first two series. Avon takes control of the Liberator. That's him in his new costume. Villa and Cally are the only crew members left over from the previous series. That's them on the right. They often have dumb looking costumes. They recruit some more new crew members in Dayna Mellanby and Del Tarrant. That's them on the left. The crew of the Liberator jaunt around the galaxy stealing and fucking with the Federation. They keep getting captured by pretty much everyone they encounter.