Yup, Ziva has definitely returned.

But the why remained fuzzy after NCIS Season 17 Episode 1.

It was certainly understandable why she had played dead after her father's farmhouse was blown up on NCIS Season 13 Episode 24.

Her body not being found after the explosion left the door wide open for Ziva's return, after whatever led to Cote de Pablo's departure during NCIS Season 11 got resolved.

A woman named Sahar wanted her dead for some reason that Ziva didn't understand.

So Ziva arranged for her daughter Tali to be sent to live safely with Tali's father Tony, which also made sense. There was no room for a young girl while her mother was on the run.

Ziva had help disappearing from Adam, whose connection to her, not surprisingly, also wasn't clear. Friend, former lover, Mossad, who knows?

NCIS: Cote de Pablo's Return as Ziva Extended

Obviously, he's a key to this storyline, and we'll find out more about him later.

What is clear is that life underground hasn't treated Ziva well.

She kept getting distracted by flashbacks, which while crucial to the exposition, certainly were an obstacle to her trying to stay alive.

Then there were those pills in her pocket, which she told Gibbs she uses to fight her "demons," whatever that means, although she hadn't been taking them since they dull her senses.

And who is Odette to Ziva, beyond being her supposed landlord?

They have history. Anyone who can rustle up a load of weapons like that has to be a former spook for some type.

Also, what's with Ziva's necklace? Is it something of sentimental value or is it some kind of high-tech device?

There's lots of answered questions still.

Yes, something has happened to Ziva in the past three years that need to be explained if we're to understand her actions, past and present.

She's not all there anymore mentally, which doesn't bode well for a long-time return. Hopefully she's back long enough to reunite with Tony and Tali before disappearing again.

Ziva had to come out of the shadows to protect Gibbs, her surrogate father and Sahar's target.

But if Sahar was coming after Gibbs, she must have had at least an inkling that Ziva was still alive and was trying to flush her out. Otherwise, why target a member of American law enforcement?

A coal chute. Clever, You just knew Gibbs would have some kind of escape route from his fabled basement. Sailing away wasn't going to work.

And of course, the two of them could come up with an improvised explosive device using just the chemicals in the basement.

Gibbs was so happy to see Ziva alive that he was willing to go along with being in the dark, at least for the time being. It's not like he hasn't had to go along with plans developed on the fly before.

Did Ziva think Gibbs would just go to a safe house and leave her to fend for herself on her mission to find Sahar?

That didn't seem too likely, did it?

Also, while it was understandable that she wanted as few people as possible to know she was alive, why not exploit NCIS resources on the sly?

As Gibbs pointed out, they were in a race to find the answers that she so desperately needed.

Where would they have been without McGee decrypting the card to find Mister Rogers' address or Kasey determining Sahar's hideout?

Although they were in the dark, Ziva's old teammates wanted to help her however they could.

It was amusing to watch how bad the team was at keeping secrets.

Bishop had done well up until now at protecting the fact that Ziva was alive, which she discovered from Ziva's note on NCIS Season 16 Episode 13.

But when Bishop started acting squirrelly, McGee just pinged her cell and found her at Ziva's old place and she had to open up to him.

Once he got over himself, then the two of them had to try to keep everyone else oblivious to Ziva's presence.

Which they did badly since Torres was wise to Bishop's tell.

Then they made the ill-conceived decision to compare notes in the lab, where of course Jimmy overheard everything.

At least Kasey had the common sense not to ask questions and to just do what was asked of course, even if she did eventually and accidentally spill the beans to Vance.

Were they wrong to keep Vance and Jack out of the loop?

It was good to give Vance deniability in case something goes wrong, which is still a very real possibility. Jack didn't know Ziva, and in the middle of a case, there wasn't time to go through all that back story.

Ziva shouldn't have lashed out at Gibbs because.there was little (but not no) reason to believe she was still alive.