Doctor Who is GREAT stuff. I started watching that series in college, in the 80s. Some of the oldest episodes are black and white. Unfortunately, there was a fire at the BBC fifteen a decade or two back, and many of the older episodes were lost. While at the time it was considered "illegal" to copy episodes, the BBC was so desperate to get the footage back that they paid people to give them any illegal copies they had made. They got many episodes back, but the series had been going on for over 20 years then, and many episodes are now permanently lost. So some of the episodes I saw in the 80s I'll never be able to see again. There are some episodes they've re-released where they have gaps, and in the gaps they've put stills with the audio in it. (For some reason most of the audio wasn't destroyed. Perhaps they stored that elsewhere, I don't know.)
The newer seasons are really good, too. Unfortunately, the only episode my sister ever watched - and she managed to catch this episode twice - was Blink. That episode scared me so much (both times that I watched it) that I had to sleep with a light on for two months! And I'm not kidding about that, really.
Btw, Wrede is pronounced "Reedy". I didn't know that, and for many years I pronounced it "Reed".