‘The Good Fight’ opens its fourth season with a ‘what if Hillary won’ episode

Adopting an anything-goes attitude from the freedom afforded by playing on CBS All Access, “The Good Fight” returns with an audacious fourth-season premiere that considers what Hillary Clinton’s election would have looked like, and the associated fallout. As what-if episodes go, it’s an especially good one, while setting up a mystery that will drive the quirky drama through this latest run.

Having spent most of last season finding ways to oppose the Trump administration, lawyer Diane Lockhart (Christine Baranski) awakens in the midst of what feels like a “Twilight Zone” episode: Hillary is president, and she’s the only one who can remember a time when things turned out differently.

What follows, though, is a pretty spot-on exploration of the Butterfly Effect — that is, when you change one thing in the timeline, other ramifications that ripple out from it. That ranges from the media and Diane’s associates nitpicking the president’s accomplishments to what Trump did after the election, and closer to home, a new ripped-from-the-headlines client for Diane who, as spoilers go, is simply too good to share.

It’s a particularly inspired flight of fancy, but it serves a purpose. Not only does it reinforce “The Good Fight’s” status as one of the smartest shows streaming into living rooms, but it allows producers Robert and Michelle King to introduce a plot that drives the episodes previewed — something called Memo 618, which appears to be a kind of get-out-of-jail-free card for the rich and connected when dealing with the judicial system.

The new episodes also find turmoil within Diane’s law firm, Reddick, Boseman & Lockhart, as the partners (including the splendid Delroy Lindo and Audra McDonald) chafe against the multinational firm that acquired them, STR Laurie. For starters, the new boss allows dogs to run free in the halls, while their offbeat representative, Gavin Firth (John Larroquette, wonderfully weird), is somehow both strangely accommodating and almost impossible to trust.

Like its predecessor, “The Good Fight” eagerly tackles hot-button issues, such as the use of the N-word by an African-American attorney in an office setting as the staff debates, among other things, reparations. While the show occasionally veers out of its lane to register those points — at times becoming a little too cute for its own good — it continues to do so in a consistently thought-provoking manner.

CBS All Access has largely relied on the “Star Trek” name to attract subscribers, but “The Good Fight” remains its best show, and that rare spinoff that’s genuinely worthy of the show that spawned it, “The Good Wife,” and distinctive enough to stand on its own.

In any TV history, alternate or otherwise, that’s a pretty impressive accomplishment.

“The Good Fight” begins its fourth season April 9 on CBS All Access.