Unity of action: The idea that goes along with this would definitely vary with what play would be put on. Whether or not to have subplots would depend upon the complexity of the main plot. A common subplot I recognize within a main plot these days is usually romance between two characters. A subplot like romance can be very simple, and not usually take away from the main plot at all. However, subplots risk the possibility of taking away from the main storyline of the play. If you have one or two it could really distract the audience because they would find themselves trying to keep track of what's going on, whose who, and the relations between characters, plots, etc. However, as I stated before, it just depends upon the complexity. At least in my eyes anyway. If you have a simple and minor subplot it could easily add a needed element to the story, but if the subplot is very thick with subject matter and things similar, it could definitely limit the play to develop to its full potential.

Unity of space: This could be very tricky. With a play it is better to have the play set in minimal key locations. With more than a few scenery changes it could easily become very complicated on stage and off stage for everybody working on the production. With a play the audience definitely has to be able to exercise their imagination, because with some plots it would be impossible to illustrate each location mentioned in the play (if there are multiple locations) Most playwrights usually have their stories set in one or two places, and other locations (if any) are only mentioned instead of displayed. I think that two, or even three locations would be enough for a play. However, as previously stated, it would have to depend upon the plot. Sometimes plays can get very boring if they are set in only one place--but that also depends on many other elements that go into making a production.

Unity of time: I'm not sure that I agree with Aristotle on this one. It really varies. This could very easily limit or welcome an advantage to a storyline. Sometimes a small part of a story is what the play is based upon, but it is implied that the storyline has stretched much further than that. A small fraction of time could simplify the play for the better so it is not so complicated, and is easier for the audience to follow. However, it could easily complicate the play by making the story line's events seem rushed, and that could hinder the audience from enjoying it. If events seem rushed it can make the play come off as very choppy, or cut & dry if you will. The use of the three unities really just depends upon the type of play being performed.