Thursday is a big day for Tesla Motors (TSLA -3.55%). At 8:30 p.m. PT, the company will finally unveil its Model 3. But don't expect to find out everything about the vehicle tonight; this is just part one, according to Tesla CEO Elon Musk. Ahead of the event on Thursday night, here's what else we know, as well as a closer look at what Musk's reference to a part one and two could mean.

Tesla Model 3 event invitation art. Image source: Tesla Motors.

Event details
While Tesla's Model 3 unveil event doesn't begin until Thursday night, the Model 3 festivities are already underway. The electric-car maker is beginning to accept in-store reservations in all of its markets where it sells vehicles. Customers can begin reserving Model 3 by putting a deposit down when their local stores open on Thursday.

For Australia, Thursday morning store openings are already here -- and reservations are already being accepted.

The event is being held in Hawthorne, California, at the company's design studio. The company says about 800 people will be in attendance. But don't fret if you weren't invited: Tesla will stream the event live on its website.

The version of Model 3 unveiled will only be a prototype, but it will be a working one. The company is offering attendees a test drive in the vehicle.

As for Musk's reference to a part one and two of the unveil, this could somewhat mirror the way Tesla introduced its Model X SUV. When the original prototype of the Model X was unveiled, the company only showed the design. It wasn't until it hosted an event to celebrate the first deliveries that Tesla shared pricing and showed off some previously unknown features, including auto-presenting front doors and the SUV's massive front windshield.

The hype is huge
Ahead of the unveil, there is a considerable amount of excitement among Tesla fans.

Before Tesla stores opened in Australia, lines had formed.

A line formed ahead of Tesla's Australia store opening. Image source: Tesla Motors.

The turnout for in-store reservations is surprisingly large considering the company hasn't even shown the Model 3 yet.

These first customers to reserve Model 3 are doing so with very little information about the vehicle. All that is known with certainty about Model 3 at this point is that it will have a starting price of $35,000, is capable of driving 200 miles on a single charge, and is about 20% smaller than Model S. These customers handing Tesla their deposits are doing so without knowing the design, available options, or performance metrics.

Enthusiasm surrounding Model 3 is also illustrated in a CNBC poll asking whether readers plan to put down a deposit of $1,000 to reserve a spot in the queue for a vehicle. At the time of this writing, 70% of respondents said they plan to make a deposit, and half of the respondents said they will follow through and actually buy the vehicle when the time comes. Currently, the survey is based on nearly 22,000 respondents.

"Looks like we may need to increase production plans for the Model 3," Musk said on Twitter on Tuesday, showing a screenshot of the CNBC poll.

Will the vehicle live up to the hype? We'll find out tonight.