Some spoilers follow for both seasons of Sugar. Sugar Season 2 is available on Apple TV now.

As detective shows go, Sugar is one of the more intriguing offerings of recent years, and not just because Colin Farrell's eponymous PI is revealed to be an alien. Through the eyes of this otherworldly sleuth, series creator Mark Protosevich endeavors to grapple with what it means to be human — the way we act, the way we feel, and the choices we make when faced with right and wrong. Do we just observe the horrors of the world, or do we try to do something about them? Must we take a life to save lives or achieve some sort of justice?

In Season 1, John Sugar faced those existential questions against a Los Angeles backdrop. His investigation into the missing granddaughter of a wealthy studio head led him to the serial killer son of a senator whose murderous machinations were being covered up, not just by powerful figures of Earth, but also by Sugar’s own people. Their secret presence had been revealed, causing some to be targeted for death while others (by the final episode) decided to return to their home world. Not John, though; he chose to stay in order to get answers about his presumed dead sister, Djen (Maeve Whalen), from his treacherous best friend, Henry (Jason Butler Harner), and to find out just who sold his people out.

Season 2 kicks off — again — in East Asia. Sugar locates a near-dead Henry, who succumbs to his wounds before the PI can learn any more about his sister. The PI looks around a hideout covered with blown-up black-and-white photos and "Beware Assimilation" painted on the wall before destroying all evidence of it and Henry in a fire. Farrell continues his velvety voiceover, waxing poetically about home, isolation, and the emotions of living, yet that warning of assimilation will hang over the eight episodes once Sugar returns to Los Angeles to take on a new case.

Protosevich certainly offers a compelling neo-noir plot for Sugar to get caught up in. This time, he's not working for the wealthy elite, but Korean-American immigrant Danny Moon (Jin Ha), a poor up-and-coming boxer whose chaotic brother, Ji (Raymond Lee), has gone missing. With the help of Sasha Calle's cool, street-smart protégé Val, and Shea Whigham's gruff, cancer-stricken government operative Tom, Sugar unearths a conspiracy involving Ji, narcotics, the sheriff's department, and the homeless community. Season 1 might have touched on the wealth gap in LA, but here it becomes part of a cogent critique of societal prejudice toward those pushed to the margins.

Season 1 touched on the wealth gap, but here it's a cogent critique of societal prejudice toward those pushed to the margins. “

Sugar has always been an empathetic hero and a sparkling-eyed contradiction to the world-weary dicks of Old Hollywood that he's long idolized, but his privilege has rarely been checked. He drives a classic Corvette Sting Ray and lives out of a Chateau Marmont-esque hotel with a closetful of pristine bespoke suits to boot. Spending time with people like Val, Danny, and Ji while navigating the less affluent sides of LA awakens him more convincingly to the very human struggle of living a good, moral life. Throw in an endearing romance with Laura Donnelly's "is she/isn't she?" femme fatale Charlotte and a vendetta against Tony Dalton's charismatic antagonist Sheriff Ray Vega, and Sugar's got a persuasively entertaining and evenly-paced storyline to rival that of The Big Heat.

Protosevich has never been subtle about how much those kinds of Hollywood films are an education on Humanity for Sugar. The alien moves with a cineliterate lens: His mind flickers to Paul Newman in The Hustler as he hustles a woman for information on Ji at a pool hall; later, Here Comes Mr. Jordan, a 1941 classic about maintaining your identity and inner worth, is playing on his TV at a moment of pensivity for what bad thing Sugar had to do to save innocent lives. Yet this meta-contemplation fails to illustrate the vivid character study of a lonely alien hiding out in the body of a human.

This is not a question of Farrell's performance. His kind gaze and warm, earnest presence evoke memories of Bruno Ganz's angel in Wings of Desire and David Bowie's alien in The Man Who Fell to Earth. Still, it's a struggle to comprehend Sugar's unease with human assimilation when the series shrouds so much of his alien heritage in ambiguity. If Sugar is worried about being too nurtured by human behaviour, what inherent nature is at risk?

It's a frustration inherited from Season 1, where many of the science fiction elements were breadcrumbed in. Here, a few flashbacks to Sugar's interactions with a rogue alien, his sister's secretive work, and a hint of his telekinetic powers are not enough to stave off hunger for meatier details about this alien race's behaviors, their backstory, and their purpose on Earth.

By the final episode, Sugar resolves his initial conundrum — and we get to see exactly why these aliens are allergic to cinnamon — but this subplot leaves us with more questions. A third season would hopefully clear those up, but maybe if Sugar was as much of an homage to sci-fi as it is to film noir, Season 2 would be a far more satisfying slice of cinematic cake.