Danno and McGarrett will be fighting for their lives on an upcoming episode of Hawaii Five-0.

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The McGarrett/Danno relationship is an integral piece of the CBS drama, and writers will pay tribute to the characters'' bond in episode 19. Titled "Ku I Ka Pili Koko," the episode will leave one half of the duo injured before the credits roll.

When a Five-0 investigation results in an explosion at a parking garage, the detective and the Navy SEAL will be separated from the rest of their team, according to TV Line. With Danno (Scott Caan) injured and little oxygen quickly running out, the pair will be in a race against time as Five-0 works to extract them from the rubble.

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Executive producer Peter Lenkov previously described "Ku I Ka Pili Koko" as a "'blood brother' type of episode," and Lenkov now claims the finished product is definitely a crowd-pleaser.

"Turned #H50 419 into the network and studio today. Prediction: Fan favorite. McDanno fans will be MORE than satisfied," Lenkov tweeted on Wednesday.

While it appears similar to the lost-at-sea plot of last season's "Lana I Ka Moana," episode 19 looks to be quite a bit darker (see photo above). Despite this, fans should relish the moment since Lenkov has indicated that McGarrett's (Alex O'Loughlin) PTSD will soon become a larger part of the plot and it looks like there is a rough road ahead for the solider.

Hawaii Five-0 airs Fridays at 9 p.m. ET on CBS. Click the video below to see a preview of the series' next episode, "Ma Lalo o ka 'ili."

Tags: Hawaii Five-O CBS television