Is it inevitable that successful Hollywood actors become caricatures of themselves? It happened to Brando, Nicholson and De Niro. And now it’s happening to Johnny Depp.

Not long ago, Depp seemed the very model of a thinking person’s bad boy – a bit quirky, more like an old-fashioned rock musician than a movie star ironed flat by the PR machine. He trashed hotel rooms, got into punch-ups with paparazzi, hung out with funky chicks like Winona Ryder and Kate Moss, accrued tattoos, played guitar, and guested on The Fast Show, refusing to play the Hollywood game.

It didn’t hurt that Brando hailed him as “the most talented actor of his generation”. And he made offbeat choices in his roles, many of which paid off. Until Pirates of the Caribbean, he wasn’t quite A-list, but he was way too cool to be consigned to the Bs and Cs.

But as Depp celebrates his half century, his separation from Vanessa Paradis has turned him into tabloid fodder, and his whimsical performance as Tonto with a dead crow on his head is being blamed for the poor box-office of The Lone Ranger. Even his red carpet choices are coming in for stick; hats, trailing scarves, tinted shades and dodgy facial hair can all seem charmingly boho and unconventional on a young actor, but on an older one they start looking a bit desperate.

Oh Johnny, where did it go wrong?

John Christopher Depp II made his screen debut in 1984, puked out by a bed in A Nightmare on Elm Street, and blended into Platoon‘s pretty boy harem before the TV show 21 Jump Street put him on the map – though obviously not in the U.K., where we didn’t watch it. [ETA: I’m told 21 Jump Street was, in fact, broadcast in the U.K. on satellite TV.] So it was no big deal for us on this side of the Atlantic when he subverted his teen idol status by playing a delinquent greaser with a facial tattoo in John Waters’ Cry-Baby.

He was beautiful. Maybe too beautiful. (He seems to have spent his life trying to cover up his flawlessness with dodgy facial hair.) Like Leonardo DiCaprio, he looked for a long time as though he has a portrait stashed in the attic. His otherworldly beauty has led to him seeming miscast as, for example, John Dillinger in Public Enemies (not a patch on Warren Oates in John Milius’ 1973 Dillinger for AIP), or as the everyman hero of John Badham’s neat little thriller Nick of Time, or the dishevelled novelist in a tatty dressing-gown in Secret Window. Though perhaps his beauty won’t be a problem for much longer – in The Tourist, I was shocked by how much he reminded me of comedian Rob Schneider.

But he was more impressive, anyway, when the beauty was hidden behind boy monster make-up in Edward Scissorhands – Bambi, Swiss Army Knife and Robert Smith of The Cure rolled into one – in the first of (to date) nine collaborations with director Tim Burton. The performance was already showing signs of the feyness that has coloured his career, but it suited the fairytale material, and it helped that he was obliged to be inexpressive.

Because I think Depp is at his best when he’s reacting rather than “acting”, when he’s a strong blank presence against which wilder players can bounce their performances. His best work is when he’s allowing others to steal the limelight – Leonardo DiCaprio in What’s Eating Gilbert Grape or Al Pacino in Donnie Brasco – or as an inscrutable anchor at the centre of oddball ensemble casts – in Ed Wood or Sleepy Hollow or Dead Man or The Ninth Gate or Rango. He’s a terrific straight man, maybe unfeasibly good-looking as audience surrogates go, but it’s those very looks that stop him from fading into the wallpaper.

I’ve been giving him the benefit of the doubt for so long, it’s only now, in retrospect, that I realise how much I dislike his “acting” – the whimsical Chaplin and Keaton routines in Benny & Joon, the Groucho-Marx-on-acid in Fear and Loathing in Las Vegas, putting on a Sarf London accent as From Hell‘s Inspector Abberline, or an Irish one as the freespirited guitar-strumming “river rat” in Chocolat. (The accents occasionally do pay off – he was credible and touching with J.M. Barrie’s Scottish burr in Finding Neverland.)

His extravagant party pieces are acceptable in small doses – such as Bon Bon, the transvestite who smuggles Javier Bardem’s novel out of jail in Before Night Falls by hiding it in his rectum – but when they dominate the film they can be disastrous. Witness Charlie and the Chocolate Factory and Dark Shadows, where he’s quirky and mannered without being remotely threatening. (Unlike Crispin Glover, whose Willy Wonka in the awful spoof Epic Movie was genuinely disturbing.)

Of his recent work with Burton, only Sweeney Todd stands out as a rare instance of the actor’s whimsical tendencies engulfed by such blistering malevolence, it makes me wish we’d seen his dark side – and I mean his real dark side, not one of his foppy-Goth excursions – more often.

The watershed, of course, was Pirates of the Caribbean: The Curse of the Black Pearl. Depp’s campy, flouncing Captain Jack Sparrow, modelled on Keith Richards, dismayed Disney executives, who thought he was ruining the film, but elevated a run-of-the-mill blockbuster into something deliciously off-kilter. Alas, box-office success demands more of the same, and so we got Jack Sparrow up the kazoo as he outstayed his welcome in increasingly dismal sequels. And now whimsical quirky Depp appears to have entirely overwhelmed the other, less showy Depp.

He’s far from a lost cause – his Hunter S. Thompson stand-in in The Rum Diary (mercifully more low-key the one in Fear and Loathing) is kept in check by fruity supporting turns. But the news that he is not only reprising his role as Captain Jack Sparrow in yet another Pirates of the Caribbean movie reprise, but reappearing as the Mad Hatter in a sequel to the egregious Alice in Wonderland is enough to strike dread into the hearts of all right-thinking filmgoers.

Evidently Depp is unaware that his arch, smug, orange-haired, lisping fusspot is an irksome lowpoint not just in his career, but in the whole of the modern fantasy genre. His Mad Hatter is not a character at all; it’s an assembly of quirks.

This piece was first posted on the Telegraph website in July 2013. It has been lightly edited. A reference to Arizona Dreams has been removed after Neil Snowden helpfully pointed out it was Vincent Gallo, not Depp, who reenacted Cary Grant’s cropduster scene from North by Northwest.

For the record, I liked The Lone Ranger, quite a lot. At the time of writing, I have yet to see Into the Woods.

My Top Ten Johnny Depp performances (in no particular order): Ed Wood, Don Juan DeMarco, Donnie Brasco, Dead Man, Sweeney Todd, Sleepy Hollow, Rango, The Ninth Gate, Finding Neverland, What’s Eating Gilbert Grape.

ETA: Alas, Charlie Mortdecai is 106 minutes of bad Terry-Thomas impersonation, and crushingly unfunny. Only diehard Depp devotees need apply.