Better Call Saul (BCS) is about the journey of Jimmy McGill from being a small time lawyer in Albuquerque, New Mexico to becoming Saul Goodman — the big time lawyer with a questionable character and slippery ethics (although this has always been true for him).
The events in BCS happen before those of Breaking Bad (BB) and are set in the same universe as the latter. If you had watched and liked BB before starting to watch BCS then chances are that you'll like this one too. Speaking from personal experience, I am a big fan of BB and I like watching BCS a lot. It is interesting how different characters from BB have started making appearances in BCS, clearing clouds over the minds of the ever so inquisitive viewers.
I highly recommend watching BB first. That's also how the creators of the show planned it — the way characters are shown in BCS, it is pretty obvious that they expect viewers to have already known about them.
Better Call Saul is best enjoyed as a prequel!
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