grammatical number - Possessive form of "one of [a list]"?

Which of the following is more correct? Or is there another form I'm missing?

We drove to the movies in one of my buddy's car.
We drove to the theater in one of my buddies' cars.
We drove to the theater in one of my buddies' car.

I suppose the fundamental question is: does this phrasing suggest "one of [the collection of cars owned by my buddies]" or "the car owned by [one of my buddies]"?

Answer

If you mean "one of the cars belonging to one buddy":

We drove to the movies in one of my buddy's cars.

If you mean "one of the cars belonging to one of my buddies" or "the one car owned by one of my buddies":

We drove to the theater in one of my buddies' cars.