Spoiler alert: The following article contains spoilers from The Rookie season 7, episode 11, "Speed."

The return of one notorious villain in The Rookie characters think they are close to ceasing Monica's reign of terror for good, she slips between their fingers. However, season 7 might finally be the end of the line for her.

New episodes of The Rookie season 7 air on Tuesdays at 9 pm ET on ABC. Season 7 is set to have 18 episodes, eight more than season 6.

In The Rookie season 7, episode 11, "Speed," Monica resurfaces after being missing since the season 6 finale. As many will recall, Monica escaped before the LAPD could arrest her in Argentina. Since that moment, The Rookie villain has been in the wind. Lopez previously mentioned that Monica evaded Interpol in Bolivia sometime before the events of the season 7 premiere. Other than that, though, Monica's whereabouts have been unknown (until her return in episode 11).

The Rookie Season 7's Cassie Debut Explained

Episode 11 Introduces The New Character

At the beginning of The Rookie season 7, episode 11, the audience learns that Nolan and Celina are going undercover. Their mission is to observe crimes committed on an LA Metro Bus and report them, while wearing plain clothes that make them blend in, of course. So, when the perpetrators exit the bus, Tim and Lucy (who are following close behind) can arrest them. Unfortunately, Nolan and Celina get in over their heads when two men with a bomb take the bus hostage, and one of the vehicle's engers is a pregnant woman named Cassie, who Nathan Fillion's character befriends.

When the Rookie season 7 characters negotiate for the release of some hostages, Denise is one of those chosen to leave. However, the police officers soon learn that Cassie isn't so innocent. In fact, her real name is Denise Summers, and she isn't really pregnant. Other than that, though, all that the cops know is that Denise is somehow related to the hostage situation.

How Does Cassie Connect To Monica & What's Next For Her In The Rookie

"Cassie" Is Working For Monica

The audience is privy to more information about "Cassie" than the characters in The Rookie season 7 are. After escaping the bus, Denise retreats to her car, where she calls Monica Stevens. Denise is working for the antagonist (somewhat unwillingly), who seemingly planned out the entire hostage situation just to get access to an ID card of a government employee, who was also on the bus. Denise gets a hold of the man's wallet before leaving and later transfers the data from the card to Monica.

Even though Denise is apprehended by the end of "Speed," Monica's return as a villain in The Rookie season 7 suggests we haven't seen the last of "Cassie."

Unfortunately for Denise, the police find her (but not before she gets rid of the aforementioned wallet and the phone she used to talk to Monica) in The Rookie episode. Prior to Denise's capture, Monica reminds her that her money is "contingent on her silence," as is her child's life. So, it sounds like Monica threatened Denise's child, which is why she is working for her. However, getting paid for her devious work is evidently very important to "Cassie," too.

Even though Denise is apprehended by the end of "Speed," Monica's return as a villain in The Rookie season 7 suggests we haven't seen the last of "Cassie." The LAPD has no concrete evidence connecting Denise to the hostage situation. And they have no idea that she is working with Monica. So, it stands to reason that the new character will return in future episodes.

Who Plays Cassie In The Rookie: Movie & TV Shows

Molly McCook Previously Starred In Last Man Standing

Molly McCook, who plays "Cassie"/Denise in The Rookie season 7, is no stranger to the TV screen. The actress has guest-starred in a plethora of shows, ranging from Glee in 2010 to Not Dead Yet in 2023. However, McCook is most known for her role as Mandy Baxter-Anderson in Last Man Standing.

Following the Last Man Standing season 6 finale, the producers recast the role of Mandy, as Molly Ephraim played the character during the show's first six seasons. Starting in season 7, McCook took over the role. Aside from Last Man Standing and The Rookie, some of McCook's other credits include The Ranch and Good Trouble.