Most sources point to underlining or italicizing; not quotes. I think that most scripts of plays are republished in books or collections (which are books).
However, that's still two different answers I'm receiving. You can always add more info after the date, in parentheses, if you think it's useful.
You also don’t need to reproduce line breaks with slashes or virgules if the passage in in prose rather than metrical verse.
If you are quoting a section of dialogue between two or more characters, you should use block quotation and reproduce the materials as they appear in your books, usually with the character’s name in all capital letters and a colon at the end of that name before each character’s dialogue.
If any of you know for sure what is expected in an MLA paper, your response is greatly appreciated. I would probably add "play" at the end, so I could jump to it using a find feature in a text editor.
Edit: The most reliable and sensible answer I found so far mentioned that back in the age of typewriters, it was underlined, but nowadays it is italicized. The safer bet would be to add the info at the end, but my preference would be to add it after the title.
The material you quote will be in quote marks, and you will uses virgules or slashes to show line breaks if it is a short quotation of three or fewer lines, or you will use hanging indentation if it’s four or more lines.
Normally, you would cite by the last name of playwright, then Act, Scene, and line number, if the play is divided in your book by such divisions and numerals and if the play is written in meter.
If any of you can confirm this notion, please feel free to do so. I doubt I would receive any complaints, either way.
Also, most of the names of works in the works cited section are italicized, articles and sections being the big exception.