WHAT IT’S ABOUT Last season, Jimmy McGill (Bob Odenkirk) uncovered a monstrous scam at the Sandpiper Crossing nursing home, and is about to lead the class action suit. Or is he? A side gig with Mike Ehrmantraut (Jonathan Banks) revived an old and dangerous urge — the “Slippin’ Jimmy” one. At least he has a good friend, Kim Wexler (Rhea Seehorn) to keep his head on straight. (Or can she?) Meanwhile, Mike has an interesting new client. The guy likes Hummers and baseball cards.

MY SAY The second season of “Saul” establishes what should have been obvious all along — this is basically just a continuation of “Breaking Bad.” Same themes. Same setting. Same preoccupations. Even same humor. But best of all, same deep, abiding intelligence. In fact, to watch “Saul” enriches “Bad,” and clarifies its meaning, and vice versa. We may not have Walter anymore, but at least we have Jimmy.

They’re exactly the same, too. Also . . . mirror opposites. Like someone from an old Springsteen song, they’re both sweating it out on the streets of a runaway American dream by day, and chasing another dream — or mirage — by night. They’ve tasted the fruit of a poisonous tree, and like the taste. “You still morally flexible?” Mike asks Jimmy. Mike already knows the answer. Jimmy does, too.

“Saul” and “Bad” are stories of transformation, but here’s the key difference — while Walter falls over the course of “Bad,” Jimmy had already fallen before his series even began. A small-time con man saved by his own morally incorruptible brother, Chuck (Michael McKean), Jimmy discovers moral clarity for the first item in his life through the Sandpiper Crossing case. Helping people in a nursing home who were getting ripped off by a depraved corporation? How much more “clarity” could Jimmy get than that? Then sibling rivalry intrudes. Their bond fractures after Chuck tries to get him removed from the case, and those angels of Jimmy’s darker nature reassert themselves.

That’s your spoiler-free setup for the second season. We already know the tragic outcome — except that we really don’t. In the opening moments, Jimmy is trapped in a garbage bin bay in the mall after taking out the trash from the Cinnabon where he works. Awaiting his rescue, and killing time, he scratches on the wall: “S.G. was here.”

S.G. still is. Another intriguing question this terrific series asks — where will Saul Goodman, and Jimmy, finally end up?

BOTTOM LINE One of TV’s best gets better.