Visible crew/equipment: When moving into their apartment Patrick Swazye kicks the statue to make it swing so they can get it inside. As they are looking at the statue, two moving men cross in back of them carring a mirror and as they pass you can see the director and camera crew in the reflection.
Visible crew/equipment: When Carl comes and takes off his shirt, he spills coffee on himself and gets half naked. As he rubs Molly's right shoulder, the scene switches to Sam in the chair. As he leans forward if you look just to the right on the marble wall, you can see a reflection of a man with a camera, blue jeans and blue shirt. No-one else was there besides those three characters.
Visible crew/equipment: Whilst Carl is sat at his computer trying desperately to access the account, a crew member is visible in the screen's reflection along with his.
Visible crew/equipment: When Sam follows Willie to his place, a crew member is reflected on the entrance door. A frame before there was no one around.
Visible crew/equipment: After Carl rips the page with the passwords, he is typing on the office computer. The reflection shows some kinds of structure with shades which disappears in the wide angles, very likely the movie's lighting equipment.
Visible crew/equipment: After Oda Mae rings on Molly's intercom she turns around and a lighting shade is reflected on her sunglasses.
Answer: Carl is laundering money for drug dealers. If the account is closed and he can't get the money back then it would be lost. The drug dealers would then most assuredly murder him in retribution.
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