Samantha begins the season pregnant with a new baby and Tabitha has some issues dealing with her new baby brother, Adam. With the advent of a new child, Samantha realizes she could use some help, so enter Esmerelda (Alice Ghostley), a shy witch without a lot of control over her powers. She has a nasty habit of disappearing whenever Darrin is around, since she thinks he hates her, plus her magic tends to wreak a lot of havoc during the season. It's pretty funny stuff.
Bernie Kopell (Love Boat) and Henry Gibson (The 'Burbs) make appearances in various roles throughout the season, as well as Jack Cassidy who plays an unflappable playboy who becomes obsessed with Samantha when flirty cousin Serena poses as Sam for a day (Ep. 194 - A Chance on Love). Very funny indeed. When Samantha's dad gives Darrin a magical pocket watch that can make him a warlock, all hell breaks loose as straight-arrow Darrin finds that a little magic in his life can be quite addictive (Ep. 178 - Daddy Comes for a Visit/ Ep. 179 - Darrin the Warlock). Funnier still is when Tabitha changes a disgruntled toy store clerk in his early 30's to a 9 year old boy because he wishes aloud to be a kid again (Ep. 191 - Just a Kid Again). Tabitha causes a good deal of trouble in Season 6, as a matter of fact, because she not only zaps herself into the fairy tale of Jack and the Beanstalk, causing Sam to have to go save her skin (Ep. 169 - Samantha and the Beanstalk), but she also creates her very own Mommy who only has eyes for her (Ep. 187 - Tabitha's Very Own Samantha).
Overall, if you are a fan of Bewitched, you'll like this season. There's a lot to laugh at here. What I did notice was that there seemed to be a stronger sexual tone at times, which I thought was odd. I guess they were trying to be 70's hip, but there were a lot of insinuations and such and even a mention of getting high in the episode where Serena kidnaps the famous 60's due Boyce and Hart so they'll play at her Cosmic Cotillion. It's certainly tame by today's standards, but I found in interesting.
If you have the previous seasons, you'll want to pick up Bewitched: Season 6 to continue completing your set.