Elementary, Blindspot, Conviction: three great Sky Living dramas, centring on very different characters. The first are a crime-solving duo, the second an amnesiac consulting for the FBI, while the third is the daughter of a former US president dedicated to uncovering miscarriages of justice.

Sherlock and Joan, Jane, and Hayes are nothing alike, yet they have one very important thing in common: when they’re on screen, you just can’t look away. Here’s what makes them so gripping.

Sherlock Holmes and Dr Joan Watson - Elementary

‘Will they, won’t-they’ working relationships are 10-a-penny in TV dramas. It’s also an oft-demonstrated truth that any dramatic tension these shows accrue will quickly unravel after that first, inevitable kiss. The dynamic that exists between Sherlock Holmes (Johnny Lee Miller) and Joan Watson (Lucy Liu), however, is different and it’s far more electric than any mere sexual attraction.

Their relationship exists on an emotional and intellectual level, but never a romantic one. This means that though the balance of power may shift over time, it’s always a partnership, and it’s this that’s kept fans watching Elementary over four seasons and counting.

Sherlock Holmes and Dr Joan Watson - Elementary

Trademark: For him, it’s the knotted scarf that says ‘Brit in New York’. For her, it’s high-heeled ankle boots and leather jackets — the uniform of a tough city girl.

Achilles heel: His addictive personality and her medical malpractice.

Most likely to say: Watson: “There’s just one question I want to ask you about your past.”

Sherlock: “Excellent, you wait here and I’ll go to my room, shut the door. Soon as you’re absolutely certain I can’t hear you, ask away.”

Jane Doe - Blindspot

When you strip away someone’s friends and family, their memory and even their clothes, what’s left? That’s the question Jane Doe (Jaimie Alexander) is answering every week in Blindspot, as the FBI team led by Special Agent Kurt Weller (Sullivan Stapleton) investigate another crime, guided by the clues tattooed all over her body.

Jane Doe - Blindspot

Drug-induced amnesia has taken away Jane’s knowledge of herself, but her innate physical presence remains.

Week by week, case by case, she’s discovering new abilities — including fluency in Chinese, Arabic and Russian — and a fearsome ability at hand-to-hand combat.

From the moment she carefully unfolds her body from the duffel bag in the middle of Times Square, Jane Doe is all elegance

Trademark: “All-over body tattoos” doesn’t quite do justice to the intricate designs on Jane’s skin, or their importance to her quest.

Achilles heel: A powerful drug called ZIP (Zeta Interacting Protein) erased all Jane’s memories, but being oblivious can also be a comfort.

Most likely to say: “What if I find out who I am and I don’t like it?”

Hayes Morrison - Conviction

Did Hayes Morrison land the top job at NYC’s newly formed Conviction Integrity Unit (CIU) because she’s a well-connected former first daughter, or because she’s a brilliant legal mind in her own right? The jury is still out on that, but one thing’s for sure: she’s used to scrutiny and never cowed by it.

That characteristic half-smile could be insecurity masquerading as confidence, or perhaps it’s confidence hiding in false modesty? Either way, it’s the inscrutability itself that’s so intriguing.

Smart-mouthed and audacious, Hayes flouts all the rules and has a ball doing it. In particular, she’s not above using her sexuality to get what she wants. And since she’s attracted to both men and women, that’s a spectacularly powerful weapon.

Hayes Morrison - Conviction

Trademark: A certain insouciance that’s hard to fake.

Achilles heel: Hayes doesn’t need anyone’s approval, with one important exception: her wannabe Senator mother, Harpers Morrison. Why else would she turn up to so many boring campaign events?

Most likely to say: “Why be the fox that guards the henhouse, when I can be the wolf that mauls the fox and anyone else who gets in her way?”