When You Know Who turned out to be You Know What in Loveless and You Know Who's Sister became the main focus it made the series a whole lot more interesting. Not better, it couldn't get better. Just more interesting.
The Avengers was better after they killed off Ian Hendry, upped the weird quotient and replaced him with Diana Rigg. I love Ian Hendry, but Diana Rigg..va va voom!
The Perry Mason Mysteries replaced Raymond Burr with Hal Holbrook. And I can tell you Hal Holbrook is the Mac Daddy of...Murder!
(And you're all wrong, Captain America is in every issue of..erm..Captain America. The Cosmic Cube transferred his consciousness into Agent 13's mind, like it did with The Red Skull and Evil Goatee Man. Nothing else can explain why she thinks that outfit is practical. It's like What If Dazzler Worked A Street Corner? Yeah, Old Stevie-boys in there getting up to all manner of naughty man-jinks. You know it. You would.)
Spooks was abit crap when the main guy from the first few series left but the latest series kicked all kinds of ass. I thought the guy who played older octavian in rome was gonna be crap cos he wasn't that good for the first episode he was in it but he was great after that.