◆ A mysterious title and stylish aesthetic initially intrigued Adamas, but the prop on which the entire show is based doesn't really serve any narrative purpose.

◆ The highlight of the series is its mystery narrative, but it abandons this in favor of tedious action sequences, then barrels to a conclusion without resolution.

When it opened in late July, the high-society action-thriller Adamas captivated us with its intriguing setup and mysterious title.

In the show, Adamas inherits a diamond-encrusted arrow from Haesong Group chairman Kwon Jae-kyu (Lee Kyung-young) that turns out to be the weapon used in a murder. The victim is the father of twin brothers Ha Woo-shin - an author - and Song Soo-hyun - a prosecutor. Both brothers are played by The Devil Judge star "Ji Sung".

"Adamas" is a Greek word meaning invincible or indestructible. It is also the origin of the word diamond. Given Chairman Kwon's extravagant hype, Adamas seems a fitting emblem for his empire. However, Kwon's iron grip on power gradually begins to slip throughout the series – becoming an even stronger symbol, as we discover that the Adamas in his possession is actually a fake.

But beyond its intriguing symbolism, Adamas is a frustrating prop. Woo-shin's motive for infiltrating Kwon's compound is to reclaim it and solve his father's murder once and for all, which is given great importance in the plot.

The Gem Arrow is also being pursued by the Special Investigation Headquarters (SIH), a secret government organization trying to take down the Haesong conglomerate. But in both cases, it's unclear how its discovery actually supports their goals.

Mystery can only take you so far, and while Adamas can be a symbolic MacGuffin to bring us into the story, ultimately the show becomes so reliant on this extravaganza that it undermines the narrative.

In keeping with Adamas’s highfalutin feel, the series’ namesake isn’t the only classical reference in the story.

Woo-shin's best-selling novel is called "Persona non grata", the Latin term for "someone who is not accepted". Appropriately, Woo-shin and his search for Adamas are unacceptable to the Chairman's house.

Adamas works best as a mystery, which means that the half of the story where Haesong is helmeting Woo-shin around the closed halls was the most compelling part of the story.

On the other hand, Soo-hyun's outside investigations and eventual dealings with SIH and Haesong's "Team A" mercenary group are dominated by action and suspense. Things quickly escalate, and throughout the latter half of the series, explosions and fires become increasingly common.

This includes Team A acolyte Yoon Sun (Park Hye-eun), a psychotic and hypocritical killer who poisons and tortures. We learn that she is the sister of Chairman Kwon's mute secretary Yoon Jin (Lee Si-won), who is the secret lover of Kwon's heir, Hyun-jo (Seo Hyun-woo).

Yoon Sun despises her sister and shares some kind of dark background with her, but it's never really explained where they came from or why they enjoy such unfettered access to the most powerful corporation in the country.

After Haesong's grand 80th anniversary celebration coincides with a terrorist attack against SIH involving Soo-hyun's friend reporter Kim Seo-hee (Lee Soo-kyung), the balance of the dueling mystery-action narratives ends abruptly.

Woo-shin leaves the complex, and with him, do many of the most interesting aspects of the show. The action anthology rises, lining up in a tired gunfight parade. We also get a long sequence featuring the characters trapped inside a shipping container while those outside try to find them – which quickly becomes one of the most overused stock suspense scenes in Korean action dramas.

Secrets begin to emerge when Woo-shin and Soo-hyun join their birth father, Lee Chang-woo (Cho Seong-ha), who has escaped from prison. The trouble is, we already know or guess most of them.

As the season nears its end, characters begin to drop like flies, and another emerges as the true mastermind. But this flurry of activity leaves many threads unexplored and even obscures those that feel rushed and unsatisfying.

By the end of the finale, not much can be explained. Instead of neatly presenting us with any resolution, the show instead chooses to end on a boring season two cliffhanger.

Judging by the show's ratings, this second season is unlikely to work. What's more, the joke at this point feels like a gimmick for the show to avoid the narrative problems that have piled up throughout its 16 episodes.

Even as it continues, Adamas lacks a sense of catharsis at the end. The origins of several characters remain opaque and their motivations puzzling. Adamas eventually returns, but by then this iconic treasure has long since lost its luster.

Still many watchers like this drama because of its strong narrative & Ji Sung's acting.