Batman who? Why The Penguin is TV’s biggest surprise of the year

HBO's DC show The Penguin is one of those rare treats that comes along almost completely unexpectedly, like Batman cracking a smile, or Harley Quinn making sensible life choices. Nobody really expected a show about the second banana in the dark knight's famed rogue's gallery to be up to much even if Colin Farrell's performance, under all those prosthetics, in The Batman was a startlingly grimy diversion from the gloomy glamour of Matt Reeves's elegant vision of Gotham City's proto dark knight. But an entire series based on Oswald Cobb's bloody rise through the ranks of Gotham City's lurid underworld always seemed a little superfluous to the main event, a spiky little sideshow to keep us entertained, deep down in the gutter with a villainous Humpty Dumpty, while DC works out what to do with the highfalutin' sequel.

Past the season's midway point, and it's clear it's more than just filler, and could yet be DC's most unexpected hit since Aquaman turned murmuring sweet nothings to swordfish into a billion-dollar box office splash . Farrell, who at times looks like Danny DeVito on a diet of gas station sushi and sheer spite, is clearly having so much fun as the Penguin that it might even make up for having to sit for three hours to undergo his daily transformation. This was supposed to be a novelty, the chance to see the Oscar nominee literally disappear into the role of Gotham's most likable dirty little rat, but the twists, turns and power struggles are so fast and fabulous that spending each episode trying to spot the handsome Irishman underneath all that silicone would be like attending a Vegas magic show just to figure out how the rabbit got in the hat.

Part of the show's success is its ability to humanise the Penguin. While DeVito's take drew empathy for his excruciatingly awful entry into life, that performance was so heavily into pantomime that we only really felt sorry for him for about 90 seconds. By contrast, Farrell's Oz might be little more than a sleazy mafioso with a waddle and an eye for destruction, but he has genuine relationships with the likes of Rhenzy Feliz's Vic, his deeply green driver and personal enforcer. He's quite content to frame his enemies for murder, or even set them on fire, but is equally happy to forgive and forget when his young aide admits he was about to skip town with his girlfriend for a new life far from Gotham. It helps of course that the lowlifes Oz spends most of his time taking down are usually even further down on the ladder of ill gotten gains than our hero himself.

Another positive here is that while The Penguin ties loosely into Reeves's version of Batman , the show has absolutely no need for multiversal shenanigans or a shared universe with other famed superheroes to ensure its success. This is an old school affair, more likely to introduce Gotham gangsters such as Rupert Thorne or Roman Sionis (Black Mask) in future episodes than it is to suddenly show us Superman soaring above the Gotham skyline. Oz is never going to jump into a spaceship and fly off to Thanagar to meet Hawkman, and frankly he's all the better for it.

And yet for all Farrell's excellence, the real showstopper here (despite being a character who might be less than well known to those not fully invested in the comics) is surely Cristin Milioti's Sofia Falcone. She's not so much a woman on the edge of a nervous breakdown as a roaring, wide-eyed, fluffy little bundle of hate - the kind of gangster in a slinky dress who after a decade stuck in Arkham Asylum (being tortured daily and punished for murderous crimes she did not commit) would probably wake up to a Godfather-style horse's head in her bed and remind herself to tip the maid.

Between Falcone and Oz, this show is like watching two scuzzy raccoons fight over the last slice of rancid pizza in a back alley from the depths of DC hell. Neither is prepared to end up second best, and both have shown themselves capable of mass murder to avoid having to settle for it. It reminds me of that scene in Christopher Nolan's The Dark Knight in which Heath Ledger's Joker snaps off a pool cue and invites two wannabe goons to fight to the death for the chance to be one of his henchmen.

One reason many fans might consider watching The Penguin is the expectation that Robert Pattinson's Batman is likely to turn up at some point to show both who's really in charge. In reality, both the showrunner, Lauren LeFranc, and Reeves have said that's unlikely to happen any time soon , but the splendid thing about the show is that we barely miss the caped crusader. This is Gotham at street level, the city's grimy underbelly exposed in all its filth and fury, while Batman's place is above the city's streets, looking down on the scum below like an avenging dark angel. Who knew that one of those unfortunate wretches scurrying about the gutter might just be capable of carrying an entire show on his doughy shoulders?

Sure, the ultimate expectation is that the Penguin will at some point climb his way up the greasy pole of power to become an A-list villain for Pattinson to take down in a future movie. But right now, watching Farrell shuffle through the shadows like a cross between Machiavelli and Harvey Weinstein after a fight with a dumpster, the whole thing is so engrossing that there's absolutely no rush.