Fiona Apple is back — and better than ever.

“The Idler Wheel Is Wiser than the Driver of the Screw and Whipping Cords Will Serve You More Than Ropes Will Ever Do,” or “The Idler Wheel” for short, was released two weeks ago, nearly seven years after 2005’s “Extraordinary Machine.”

Apple and her band are on an ambitious tour that stopped Sunday night at the State Theatre. I would be remiss if I didn’t start by saying that it was sweltering hot in the theater, but given that Apple is such an inferno herself, it somehow seemed fitting.

Wearing a blue pleated slit skirt, red sleeveless top and some serious black boots, Apple started the show off with the hit “Fast as You Can” from 1999’s “When the Pawn ” album. Halfway through the song, she made her way over to her grand piano and went to town on it.

“I think the smell of sweat is wonderful so let’s just enjoy it,” she said when the song ended, to much cheering.

Soon after, Apple played one of the songs that first got our attention back in 1996 when she released her debut “Tidal” album.

“Shadowboxer” was the tune and it got the near sellout crowd swaying, despite the heat.

The next moment of Apple brilliance came in the form of “Get Gone.” She has the vocal ability to go from a whisper to a scream and back again, and she wields it sometimes carefully and sometimes with gorgeous, reckless abandonment.

Stomping around moments later as she sang the crowd-igniting “Sleep to Dream,” Apple had us right where she wanted us — or maybe even just where we needed to be — and kept us there for the remainder of the show.

Sometimes she’d dance around the stage with a wild-eyed look on her face; other times she’d assume a yoga-like face down pose down on her knees. All the while, she’d be singing her heart and soul out.

Speaking of singing, at one point the audience was scolded with, shall we say, colorful language, for singing too loud which Apple found distracting.

But because she was clearly putting so much of herself into the show, rather than take offense, the crowd did as she asked and was rewarded with the first song from “The Idler Wheel,” “Every Single Night.”

You’ll never hear another singer pack more of a punch into the word “brain” as Apple does on that one.

One of Apple’s best-known songs is “Criminal,” and she could have easily just stuck to an album-sounding version of it, but instead she busted it right open and laid it bare with some of the rawest vocals of the night.

That’s the thing that makes Apple such a compelling performer, the way she breathes fire in one moment and then brings it down with a moody ballad.

Apple’s known for forgoing encores at her shows and this night was no exception.

But I had to hand it to her for ending with a fabulous rendition of the Conway Twitty song “It’s Only Make Believe.”

To hear her sing the words “My only prayer will be, some day you’ll care for me, but it’s only make believe” was so ironic, given that from where I sat there was a whole lot of love directed her way.

Welcome back, Fiona. You’ve been missed. And thanks for bringing such a terrific band with you, including your guitarist and opening act, Blake Mills.