Robbing Blockbuster

Okay, nitpicks first:

MOVIE STORE CASHIER: It’s a school night, isn’t it? It’s a little late to be checking out movies.

He had directed the question to REUBEN, but REUBEN doesn’t look up from the shelves. ALEX notices the MOVIE STORE CASHIER looking at REUBEN.

Aren't both of the guys teenagers? So why did he direct the question merely at Reuben but not at Alex?

MOVIE STORE CASHIER: It should be right here. He crouches down to search for the movie. Ah. Here you go. He slides out a movie and hands it to ALEX.

This is probably very very nitpicky, but...

Didn't the cashier say that they had 'some' movies, not just one? So shouldn't he slide out a few? I don't know, these little coherence things always bug me.

REUBEN fires a bullet, and the MOVIE STORE CASHIER freezes.

Where does he fire it? When I read it the first time, I thought he fired it at the cashier.

REUBEN: What the hell? How do you open this thing?

Haha, that's pretty stupid of him... If humour was intended... XD

Crap crap crap! Mister? Are you okay? I—I don’t have my cell phone! Do you have a phone here? I’ll call an ambulance and the cops. Crap crap crap!

I don't know, the repetition of crap in such a consistent manner makes it rather humourous.

ALEX: Hello? Oh, thank God! There’s been a robbing at Blockbuster, and the robber shot the cashier, and I’m the only one here. Yes. Yes. No! I don’t know who he is. He pulled out a gun and robbed the place! ALEX begins to cry. I don’t know! Okay. Yes, I can hear the sirens. They’re coming around the street. Okay, thank you so much.

I could somewhat relate and bear the fact that the receiver of the call could trace their location, but I think it would be safer if you had Alex told him/her their location in the first place. Furthermore, the ambulance/police is arriving too too soon. One more thing: if he's in a panic, I don't really he would be so clear in his dialogue. Make him trip on his own words and thoughts.

~~~

Overall:

I don't know. It felt kind of two-dimensional. I understand that tension is what you are aiming for, but then everything seems too flat. I liked some of the nuances you added to your dialogues, but there are times where you could enhance it more.

Characterization could use some work too. All of the characters were so typical without their own quirks.

Other than that, I don't know what else to say. It was a good attempt. Good luck.