Katsumoto needs Magnum and Higgins' help when his ex-wife Beth is held hostage. The kidnappers want Katsumoto's former partner dead, otherwise they'll kill Beth.
Meanwhile, Rick loses his cool as Suzy goes into labour. But there are complications...
Tropes:
- Artistic Licence – Geography: The sunset that presides over the Big Damn Kiss shouldn't have been there as the building is facing south.
- Big Damn Kiss: Magnum and Higgins, on the hospital rooftop at sunset, closing out the season.
- Bittersweet Ending: Katsumoto may lose his career in law enforcement for breaking Whelan out of prison, but Beth is safe so he decides he can live with it. Meanwhile, Suzy is narrowly saved by surgery after delivering a healthy baby girl named Joy, and Magnum and Higgins have their Big Damn Kiss.
- Call-Back: When Katsumoto is about to shoot Nasano in cold blood for what he did to Kim, Magnum reminds him of a time he talked Magnum down from the same thing.
- Corrupt Cop: Katsumoto's ex-partner Whelan. He's in the process of cutting a deal with the Justice Department, which is why he needs to go.
- Great Escape: When time is about to run out on killing Whelan, Magnum has a plan; kidnap Whelan instead and use him as bait to lure out the kidnappers. Great in theory, with just one problem; Whelan is in prison.
- The Guards Must Be Crazy: None of the prison guards seem to notice that Magnum isn't one of them.
- I Have Your Wife: Matsumoto's ex-wife is held hostage to force him to kill his ex-partner, who's in prison on corruption charges.
- Love Confession: In the very last scene of the season, Magnum and Higgins declare their feelings for each other and kiss.
- Maternity Crisis: Suzy starts bleeding out after delivering her and Rick's baby and is rushed into surgery.
- Oh, Crap!: Magnum, when he realises his route to the part of the prison he needs to access goes right past two inmates he helped put away.
- Why Did You Make Me Hit You?: Nasano's attitude when he shoots Beth in the arm for getting Magnum and Higgins involved is that it's Katsumoto shooting her, not him.
- You Killed My Father: Katsumoto learns that his sister, Kim, was murdered by Nasano to throw him off his game as he was getting too close back when he and Whelan were investigating him. He almost kills Nasano for this, but Magnum talks him down.
