Referring to the crisis, Michael says it's threat level midnight and Jim smiles at the camera. In The Client (2005), Pam finds a screenplay written by Michael, titled "Threat Level Midnight" and subsequently Jim organizes the office in a reading of the screenplay.
When Creed is framing Debbie Brown for failing to spot the watermark, he tells Dwight that Debbie cited an "emergency dentist appointment" as her excuse for missing work. Dwight is rightly suspicious of this, because this is the same excuse he uses on Michael when he lies about going to meet Jan in The Coup (2006). He tells Michael he needs an "emergency crown" placed by "Crentist the Dentist."
The poster Dwight holds up for Michael's apology video reads: "I need this job. My mortgage is hundreds of dollars a month. With this job I can barely cover that. I have a company car, but I still have to pay for the gas. Gas prices are high and I have no savings whatsoever. And it wasn't even me. It's so not fair that they want me to resign."
Angela realizes that Kevin made an error adding 4 and 7. This has nothing to do with Jim's costume, since it was a payroll form and not an expense form. They both just happen to have the same numbers.