Cullen and Tolbeck are finally given the chance to save the day. Marco and Frankie consider their options, while a new - but not necessarily improved - Janice returns to Dispatch.

Cullen and Tolbeck make a shocking discovery. Fatima is jealous of Zach's newfound success. Marco comes clean and his situation with Frankie comes to a head.

Zach, the new dispatcher at SDPD, goes to various lengths to impress Fatima. Cullen confronts Tolbeck, who admits a shameful secret.

Marco puts the entire cockfighting ring in jeopardy and must find a solution before it's too late. Fatima is forced to undergo sensitivity training. A dream scenario for Cullen and Tolbeck turns nightmarish.

When Cullen and Tolbeck are reunited with a figure from their past, Cullen realizes that he doesn't know his partner at all. Meanwhile, Marco and Frankie open up to each other, and Janice finally unravels.

Marco and Frankie are victims in the nicest hostage situation ever. Fatima inserts herself in the middle of an awkward love triangle. An annoying visitor joins Cullen and Tolbeck in Car 27.

Season finale. After losing yet another key witness in the Las Hormigas Cartel investigation, Cullen is forced to deal with the consequences... and FBI agent Dustin Kasprowicz. Janice returns to Dispatch to confront Clint and delivers shocking news.

The night of the cockfight arrives with unexpected results. Janice blames Fatima for her financial woes. Tolbeck has an unlikely admirer.

Detective Cullen decides that it might be best to finally part ways with Tolbeck. A surprise visitor disturbs car 27.

It's the night of the raid and Detectives Cullen and Tolbeck are intent on being the hero cops who break the drug ring.

Car 27 stakes out a cockfighting ring. Cullen and Tolbeck are rattled when a hero of the San Diego Police Department falls from grace. Both Marco and his new partner-in-crime, Frankie, have a secret. Fatima falls victim to extortion.

In this documentary from Jürgen Leibbrandt, the FBI investigates supposed cult The Collective and seeks the truth behind who really shot Agent Risoli.

Detective Tolbeck is forced to confront the problems in his marriage as the pending raid draws near.

Cullen tries to set boundaries as a worse-for-wear Brock comes to terms with his new reality. Meanwhile, Janice's frustration with the invasion of BopBot intensifies and Chief and Gary need to rectify a huge mistake.

Leon throws himself a retirement party but Cullen and Tolbeck are wary of his intentions. Clint confronts Janice about her hatred for the BopBot, but the conversation quickly turns into a rehash of their romantic past.

Disgraced and behind bars, former detective Josh Haldeman is interrogated by Agent Kasprowicz. Back at Dispatch, Clint and the BopBots have successfully infiltrated the department and everyone's job may be on the line. On a stakeout, Cullen is stuck with a less than enthused new partner.

Detective Cullen and Fatima recall their first date with vastly different versions of events.

While Detective Tolbeck is seeing a therapist to discuss the shooting at the docks, Cullen is partnered with Senior Detective Bonnie Lyman.

Cullen is tasked with helping Officer Charles Brock extradite a key witness in the Las Hormigas Cartel investigation but all hell breaks loose at 30,000 feet. Back at Dispatch, Clint begins to shake things up by introducing new technology to the department but not everyone is quite as thrilled. Still in the hotel room, Chief and Gary try to stay occupied while awaiting their target.

As Cullen and Tolbeck prepare to give Doris' family the news that she is finito, they get a surprise visit from FBI Agent Dustin Kasprowicz. Meanwhile, Gary and Chief strategize their next move and Janice tries to convince Fatima that they may need to start looking for new jobs.

Following the shooting, Detective Tolbeck waits nervously for Internal Affairs Investigator Leon Fordham to arrive.

Det. Cooper fills in the blanks of last night's events to a woozy Cullen while Dirk finally meets Terry. Janice and Fatima return to dispatch.

With the docks now compromised, Detectives Cullen and Tolbeck are re-assigned to warehouse surveillance in the Otay Mesa area.

After reuniting, Cullen and Tolbeck realize they have information that could take down The Collective.

On Night 35 of a drug stakeout at the San Diego docks, Detectives Cullen and Tolbeck find themselves waiting on a Mexican cartel drug shipment.