Step into the TARDIS and meet its latest passenger: Bill Potts.

A lot of this has to do with our latest companion: Bill Potts.

In response, Bill ends up asking whyhecalledher.

Doctor Who S10 Ep1

Credit: Simon Ridgway/BBC AMERICA

Shes not the only one to unofficially audit his classes.

He answers that shesmilesinstead of frowns when she doesnt understand something.

The long and short of this is that he wants to be her personal tutor.

And hell see her every weekday evening for classes.

Doctor What also warns her that hes very particular about time.

Heather seems upset about something.

After Bill inquires what, she says she wants to leave Bristol and go anywhere else.

She also wants to show Bill… a puddle?

Once at the puddle, Heather asks Bill to tell her if she notices anything about it.

Bill senses something but cant quite put her finger on it.

As the Doctor would probably note in his lecture, Time and Relative Dimension in Space!

It gets better when Bill asks him heknows any sci-fi.

Her theory is Heather has been possessed by a lizard creature.

When she says this I immediately wonder: Does theDoctorhave Netflix?

Is it unlikely animal friendships?

I hope its unlikely animal friendships.

But my fanciful daydreaming aside, the Doctor has figured out the problem: The reflection is too symmetrical.

Things arent reversed like a mirror.

To this, Bill brings up a very good point: If thisisnta reflection… why does itmovelike one?

In any case, the Doctor takes a sample of the puddle and notes its not water.

Looking around, he notices that there are scorch marks in a circle…

He dismisses Bill and sends her home.

Only that isnt safe.

She hears the shower, but quickly learns that itsnother mother in there.

So Bill investigates only to see a shape behind the shower curtain.

Alarmed, she bursts into the Doctors office and tries to block the door.

Despite her argument that its made of wood, and there are windows.

The proud Doctor announces that shes safe in here and always will be.

With the score playing and the triumphant tone of his voice, its hardnotto believe him.

As Nardole joins them, the Doctor begins their hasty getaway from Heather.

The first location he chooses is the vault, to check on it.

But Bill is convinced Heather isnt after it.

So the Doctor takes them to Australia.

And doing some A+ Whovian stand-up.

But this oddly sweet moment is ruined by Heathers arrival.

So they blast off to the edge of the universe threemillionyears in the future.

Heather shows up again.

Much to Nardoles amusement.

They also figure out that the puddle was a super-intelligent oil leak.

Its just acting on Heathers wanderlust.

The Doctor doesnt know.

Turns out the location of this is in the middle of a Dalek war zone.

It doesnt seem to have much effect as she starts mimicking the Dalek.

They run off again, but with a Dalek in pursuit.

Only its not one.

Its Heathers having taken it over.

The Doctor says it best: Never underestimate a crush.

So it turns out that Heather is inviting her to travel with her.

Just like that, Heather washes away.

The Doctor checks up on Bill, but she says she thinks shes fine.

Nardole also checks up on her, to which the Doctor gets annoyed.

But he tells her that fear is a good thing to have.

To this, he lets her go and tells her to run.

Has all the time and space traveling finally caught up with our favorite Time Lord?

Though the fact that he was hes here undercover (presumably for50years) guarding (or investigating?)

the vault and that hes promised not to do that anymore is a bit concerning.

Whats going with the Doctor?

With that, he snaps his finger, the door flies open.

Bill takes his and steps into the TARDIS, officially kicking off the seasonandtheir adventures together.

(Like a pen holder full of the Doctors previous sonic screwdrivers on his fancy new desk?)

Theres also a basis of a slowly developing bond, which I really like.

But we also see it in the Doctors treatment of her.

When he first met Clara he was absolutely rude.

Nardoles inclusion this season is also a continued delight.