Laskey is a rookie cop with whom Carter is initially reluctant to work. He is given strict instructions by Carter not to help when she doesn't need it and not to use any equipment in her car. He is seen to have vomited at the sight of a corpse found on the street that had been shot several times.
Later, as he appears to want to be her partner, she seems to warm up to him. He tells Carter that there were other rookies who turned down the offer, but he chose to work with her. He claims to be amazed by what he learned about Carter working in the Homicide Task Force, and that he wants to do something good like take down dirty cops the way Carter did. Touched, Carter allows him to operate the radio and respond to one of the calls made before they drive off to investigate. (“Nothing to Hide”)
Laskey surprises Reese and Carter as they meet in an alley to discuss a POI, Vanessa Watkins. Afterward, he meets with Raymond Terney and reports that he has Carter's trust, and has seen her "with her boyfriend." (“Reasonable Doubt”)
One day on patrol, Laskey flashes a new nickel plated .45 caliber handgun he purchased in New Jersey. Realizing he has not registered it properly in New York, Carter takes it from him. Soon after, Laskey tells Carter he wants to have a private talk with her at a local bar. He reveals he knows Carter is working to bring HR down and he's been cleared to kill her, and the bartender is in collusion.
Carter, in turn, tells Laskey she knew he was up to no good from the beginning and that she knows the bartender is HR backup because Laskey was afraid to face her alone. She goes on to list the bartender's crimes from his HR days. When that prompts the bartender to pull a shotgun on her, Carter kills the bartender with the gun Laskey purchased, framing him. She warns Laskey that he now works for her. (“Razgovor”)In a Russian neighborhood, Laskey's friend from childhood, a shop owner named Morozov, is skimming from HR without Laskey's knowledge. Patrick Simmons sends Laskey to issue a warning with Carter watching, but claims not to speak Russian, making Carter suspicious. He tries to convince her HR is about loyalty, among the Russians like Morozov, who's owned that deli for years and within the police force. Since Carter is more familiar with the inner workings of HR, she warns him that he'll soon learn what they really expect when they say "loyalty." Later, Simmons tells Laskey he killed Morozov, and orders Laskey to bury the body in a place where no one will find him. A visibly shaken Laskey confesses to Carter, revealing his Russian origins and the fact that HR is using Russians in the police force to bolster their ranks and their alliance with the Russian mob at the same time. She warns him that this won't be the worst HR asks of him. He wonders, "What could be worse than burying a friend?" (“Mors Praematura”)
Laskey is called to a meeting with Terney and Simmons which is monitored by Carter through her forced pairing of Laskey's phone. Terney and Simmons offer Laskey a chance to get more involved in HR's operations by helping them deal with a money launderer who messed up. Laskey, continuing to be monitored by Carter through his phone, sits in an auction with Terney who points out Sven to him and tells Laskey he will kill Sven the next day.
After Carter returns from her meeting with Elias, Laskey questions who she is always meeting with then tells her that can't commit murder. Laskey admits that he "looked the other way" as a member of HR but can't do that anymore and asks Carter for help as she's the only one on his side. Carter tells Laskey's she not on his side but she won't allow him to commit murder either. Instead, Carter assigns Laskey to follow Simmons and take pictures of everyone he meets with in hopes of finding the head of HR.
That night, Laskey gets a picture of Sven "dead" and a text from Carter ordering him to tell Simmons that he killed Sven. Moments later, Simmons calls to tell Laskey to hold off on the assassination as there is a problem with Sven, but Laskey tells him that Sven is dead and warns Carter that Simmons knows about the stolen baseball. The following day, on Carter's instructions, Laskey calls in sick from work and takes several pictures of Simmons meeting with people, getting a picture of Simmons meeting with HR leader Alonzo Quinn about the situation HR is in.
After HR kidnaps Natalie Boal, Laskey is called in as one of the HR cops to deal with Natalie and Hayden Price. As Terney heads inside with two HR cops and Hayden, Laskey is left alone with Natalie and orders to kill her after HR gets proof that the baseball is real. Carter approaches Laskey with Shaw after the HR cops are gone and Laskey tells Carter that she was right that HR would never let Natalie go. Now fully on Carter's side, Laskey tells Carter to knock him out and "make it look good." Carter then punches Laskey unconscious.
That night, Carter and Laskey meet in the lobby of his apartment building where Laskey hands over all the pictures he took of Simmons. Carter admits Laskey did good but warns that things will only get worse with HR after the past few days. Laskey is prepared, telling her he'd thought that HR was about loyalty but he now understands that its about murder and greed. At that moment Terney, looking for Laskey in order to enlist his help with finding the stolen baseball, enters, having overheard that Laskey now works for Carter. After taunting Laskey, Terney tells him that they have to kill Carter or HR will kill them. In order to back Carter up, Laskey draws his gun but Terney shoots him in the chest as he draws, killing Laskey as Carter returns fire. Carter is grieved to find Laskey already dead when she takes his pulse and asks the mortally wounded Terney if one of the people Laskey photographed is the head of HR. With his dying breath, Terney marks Alonzo Quinn in Laskey's pictures as the leader of HR. (“The Perfect Mark”)
After the deaths of Laskey and Terney, Carter set it up so that it appeared as if the two had killed each other. Meeting with Alonzo Quinn, Carter claimed that she didn't even know Laskey and Terney knew each other let alone had a problem with each other. During the meeting, Carter cites Laskey's death as part of her reason for stopping her investigation into the murder of Cal Beecher while really using the opportunity to perform a forced pairing of Quinn's phone to further her investigation into him. (“Endgame”)
- In casting calls, Laskey was described as "Carter's new rookie partner Avery, who looks young and innocent but has some dark secrets."
- Carter frames Laskey for the murder of a corrupt cop and uses him as her informant about HR, similar to how John Reese framed Lionel Fusco for Detective James Stills's murder. (“Pilot”) Like Fusco, Laskey eventually realized that HR was the wrong side but didn't survive to become an honest cop as Fusco did.
- After learning that Sven Vanger was "dead" and Laskey had "killed" him before they could find out the location of the stolen baseball, Alonzo Quinn humorously suggested that Laskey take Simmons place in HR because he could at least follow through on things. It was also during this conversation that Laskey took the picture of Quinn that Terney used to identify him as the head of HR. (“The Perfect Mark”)
- After the HR takedown, Laskey is one of the HR cops displayed on the Machine's HR graph. Laskey is listed as deceased with his real name and the fact that "Mike Laskey" is an alias. (“The Crossing”)