Season 1, Episode 3:
Reese and Finch try to figure out how to help Joey, an Iraqi war vet that's fallen in with a group of ex-military bank robbers. Their middleman, Latimer, enlists Joey's gang to steal a single item from a police lock-up: a box of evidence from the murder of "Elias, M." Reese infiltrates the gang for the heist and Finch tries to intervene, getting caught as one of the hostages. When they return with the evidence, Latimer tries to kill the gang but Reese manages to save Joey and convinces him to leave town.
In the coda, Latimer delivers the evidence to his mysterious employer: crime scene photos from the 1970s of a woman found dead in her home, along the murder weapon, a kitchen knife. Latimer demands his payment, but when Reese tracks him down, he finds Latimer's dead body, killed with the kitchen knife.
In flashbacks to 2006, Reese is on his way through an airport when he runs across Jessica, his former lover; she's currently engaged to someone else, while Reese is on his way to some top-secret deployment. Jessica is still in love with Reese and offers to stay if he asks her too, but he can't, not until she's already gone.
Tropes present in this episode include:
- Bank Robbery: The episode opens with Reese getting caught in the middle of one when he tracks the current POI into a bank, the POI puts a mask on, and three other men hold the customers and tellers at gunpoint.
- Brick Joke:
- Reese suggests that Finch should get some exercise. Later, Finch is shown doing pushups in the library. And then he denies it when Reese asks what he's doing.
- Reese facetiously suggests 'dog walker' as a possible job for Finch, who in later seasons is seen walking Bear a lot.
- One that doesn't come due until almost the end of the series. Joey does in fact meet a reclusive billionaire similar to Finch, and the two establish their own Team Machine operating out of Washington D.C.
- Chekhov's Gun: Reese's Glock 18.
- Cool Guns: Latimer's crew pack Heckler and Koch MP5K PDW submachineguns, which he sabotages. Reese also gets in on the act bringing along a fully automatic Glock 18 machine pistol which becomes critical in the climax of the episode.
- Doomed Hurt Guy: Dalloway is wounded in the leg during the robbery and soon afterwards killed in the fight with Lattimer.
- Even Evil Has Loved Ones: Straub is the sleaziest of the crew besides Lattimer himself, but he has a mother whose property he put up for gambling collateral, and which he wants to save from being seized by the gamblers.
- Faux Affably Evil: Lattimer does a good job coming across as a Punch-Clock Villain who genuinely cares about his men, but has been cold-bloodedly betraying them without remorse.
- Framing the Guilty Party: How Finch creates an opening in the gang for Reese to fill.
- The Gambling Addict: Straub has a lot of gambling problems, which is why he's still doing heists.
- Honor Before Reason: Joey robs banks, putting his life and liberty at risk, to provide for the family of a deceased Army comrade.
- I Will Wait for You: Jessica's promise to Reese - all he has to do is ask. Sadly, he can't bring himself to say it and she leaves in tears... and then he says it after she's out of earshot.
- Innocuously Important Episode: While "Mission Creep" isn't the most stellar offering in season 1, the case files of the "Elias, M." murder kick off one of the major arcs of the first season.
- It Works Better with Bullets: Joey and the gang have a hard time fighting back against Latimer when their guns have no firing pins. Luckily, Reese brought a second gun with enough fire power to drive Latimer off.
- Laser-Guided Karma: Lattimer finding out that he isn't immune to You Have Outlived Your Usefulness.
- Manly Tears: Tears can be seen brimming in Reese's eyes as Jessica leaves.
- Mission Creep: The title of the episode which shows the trope in action.
- Properly Paranoid: The bank robbers.
- Put on a Bus: Literally. Joey and Pia get out of New York.
- Removing the Earpiece: Reese is forced to hand over his ear-comm when the gang destroy their mobile phones. Finch has to go directly to the place they're robbing to pass on his warning about Latimer's intended betrayal.
- Sheep in Sheep's Clothing:
- Detective Molina is introduced as a reasonable, competent man who quickly allies with Carter, but the fact that Lattimer is taking orders from someone (not to mention robbing a police evidence locker) might make him a bit suspicious. But in fact, Lattimer's boss is an Arc Villain who won't actually be seen for several episodes while Molina is the honest cop he appears to be.
- Reese himself. In the opening robbery he silently tells a guard to not fire his gun so he won't be killed. That makes Carter believe that he's an inside man.
- Stealth Hi/Bye:Finch: Don't you knock?
Reese: Not if I can help it.
- Wham Line: Detective Molina talking about how Manny and Danny, two of his suspects in the robberies, turned up dead, men Lattimer claimed had retired with their proceeds of the money) and revealing that they were murdered casts a very different light upon the heist crew and why Joey's number came up.
- You Have Outlived Your Usefulness: Latimer to the gang of robbers, and then Elias to Latimer.