ALEX PARRISH

There's smart and there's smart. Alex Parrish, the leading lady of big new US drama Quantico, is definitely the latter. She may be a rookie FBI agent with considerably less crime-busting experience than the other heroines on our list, but Alex Parrish has a predatory instinct for rooting out lies and hidden agendas. In fact, when it comes to on-the-spot deductions, she would give a certain Victorian pipe-smoking sleuth a run for his money.

Add to that her natural charisma, her unashamed lust for life, and a mysterious backstory involving an tyrannical father who may or may not have been working for the FBI himself, and you've got one of the coolest characters to grace the crime genre. Oh, and on top of all that she's framed for a terrorist outrage and has to solve the biggest crime of her times while on the run from gun-toting federal agents. Respect is owed.

JANE RIZZOLI

Hailing from a blue collar Boston background, Jane Rizzoli is one of the toughest cops on TV. With her fiery Italian-American nature and a brash approach to her job that comes from being brought up in a no-nonsense household, Rizzoli takes no prisoners (except when she, you know, literally does). Calling her a "tomboy" doesn't really do her justice, because you can't really pigeon-hole someone as independent and gutsy as Jane Rizzoli, especially with what she's been through.

Lest we forget, we're talking about the woman who sports scars on her hands from the time she was attacked by a psychopathic, scalpel-wielding serial killer. And that's just one of the skirmishes she's survived. It's a wonder she still has an appetite for her job, but then again she does have the significant career perk of working alongside her BFF and soulmate. Which brings us neatly to...

MAURA ISLES

The other half of Rizzoli & Isles isn't a cop at all. Maura Isles is actually a forensics expert, and has always been obsessed with all things science. This didn't go down to well at school, where she was nicknamed "Maura the bore-a", but her passion for probing dead bodies has led her to a grand career as a crime-solver alongside her best bud Jane Rizzoli.

The two are beautifully mis-matched - where Rizzoli is a tough urban warrior, Isles is a softer personality with a penchant for dressing up like she's about to take to the catwalk at a moment's notice. Seriously, even just lounging around her house she looks impeccably well put together. You've got to love a character who's unashamedly brainy and unfeasibly fashionable while also being genuinely a bit odd - remember the time she literally didn't know what peanut butter was? This is why Jane once called her "the dumbest genius I know". Awww.

KATE BECKETT

Castle may be called Castle, but we're going to go ahead and say that the real star of the show is his crime-solving partner (and later wife) Kate Beckett. She's so relentlessly great it's hard to know where to start. Is it the way she's a kick-ass cop who's taken down half the bad guys in New York? Well that's all in a day's work. What we really love about Beckett is all the other stuff - like the fact she's a total, out-and-out nerd girl. She has a particular thing for a Star Trek-like sci-fi show called Nebula-9, and Castle fans will never forget the moment she got into some serious cosplay as a Nebula-9 alien (complete with terrifying mask).

She also has informed views on comic books, with a particular love of Marvel character Elektra. "Ah, a ruthless assassin who hides from her emotions," Castle quipped on finding that out, while clearly loving her geek credentials. As do we, because it's fantastic to see the tough, homicide detective lead of a crime series who has real, actual passions that real, actual people do. Who'd have thought it?