What a great twist!

Sherlock and Joan found an innovative way to reboot their partnership on Elementary Season 6 Episode 21.

After six years in New York, maybe it is time for them to have a change, as this soft cliffhanger suggests.

I was expecting something grander for the finale. Why have Morland stop by and mention Moriarty's machinations if you're not going to go back to them?

Also, I expected Mycroft to be resurrected somehow. You can't just erase such an important character from the Sherlock Holmes canon.

Still, the identity of Michael's killer was reasonably simple once you broke it down.

Related: Elementary Season 6 Episode 20 Review: Fit to Be Tied

Who wanted Michael dead?

Yes, Sherlock and Joan were good, obvious choices. That's why they should have been dismissed immediately. But Malick was too linear a thinker for that to happen.

As injured as Joan was, she was supposed to be able to get the drop on Michael, who granted was also injured? How did she even know how to find him? She and Sherlock hadn't had much luck doing so when Michael didn't want to be found.

Was Michael's yelling out Joan's name one last challenge for Sherlock to solve before Michael's passing? Probably. It was damn hard to explain away.

But let's just eliminate the two leads right off the bat. It had been announced months ago that Elementary Season 7 was planned, so Sherlock and Joan were safe.

Still, as events played out on this episode, apparently they are the only ones sure to come back.

Related: Watch Elementary Online: Season 6 Episode 20

OK, so who should the suspect pool in Michael's murder include, for an investigator more thoughtful than Malick? I know. How about all the friends and relatives of Michael's murder victims?

Most of them lacked the skills to stalk a cunning serial killer such as Michael. So that would leave ... Hannah Gregson, a  veteran cop whose best friend was killed by Michael to get Sherlock's attention.

Here was the problem, however. While Sherlock and Joan were investigating Michael's murder, he was destroying evidence along the way.

And, unknown to them, so was Captain Gregson, to protect Hannah. He had no idea that Malick would turn around and make Joan her prime suspect.

So that left Sherlock and Gregson working at cross purposes, trying to save the ones they loved.

They could have done so much better working together. Unfortunately, there was no obvious person to set up as the murderer. Nor would they do such a thing.

Related: 13 Excellent Partners in Crime

Marcus was wasted in this episode. He was reduced to snarking at the bullheaded FBI agents, while Malick threatened his future career path. He supplied Sherlock with what little information he could smuggle out, but with Gregson and Sherlock undermining the FBI, there wasn't much to be had.

After watching all the cases Sherlock has solved around the 45-minute mark, I found it hard to believe he couldn't have found a more elegant solution this time around.

He played his get-out-of-jail-free card by confessing to Michael's murder, which was somewhat appropriate. He created Michael, however inadvertently.

It was a treat watching Sherlock emote, something he usually does badly, allowing all his feelings for Joan to emerge. She was pissed at him for making such a large decision without her, but she was touched at the same time by his confessions.

There was something right about having Sherlock back living at 221B Baker St. It was an unexpected treat to discover that Joan had followed him across The Pond to continue as his partner. And didn't she have on a perfectly British outfit?

With the Scotland Yard characters that have been introduced both on Elementary and in Sir Arthur Conan Doyle's novels, there is a strong foundation for a season based in London. I'd love to have them borrow Sean Pertwee from Gotham long enough to have Lestrade visit a time or two.

Related: Get CBS All Access via Amazon Channels for Hit Shows, Exclusive Originals & Live TV! 

That said, I don't expect the London setting to linger the whole season. Some piece of evidence will turn up that exonerates Sherlock, and the case will go back into being unsolved. Which agency is willing to put that much resources into the murder of a serial killer?

Still, things would have to change. Gregson betrayed Sherlock and Joan, without meaning to. Maybe he retires, the better to keep an eye on Hannah. Then Marcus gets kicked up to captain and gets a new protege, and the relationship between the NYPD and Sherlock and Joan is renewed.

That's two scenarios to breathe new life into Elementary.

To savor the New York years, watch Elementary online.

Were you surprised by Michael's killer? Who had it worse? Would you like to see Elementary set in London? 

Comment below.

Dale McGarrigle is a staff writer for TV Fanatic. Follow him on X.