It’s confirmed: three decades after he last donned the pointy-eared cowl, Michael Keaton is going to play Batman once again, in upcoming Warner Bros/DC movie The Flash. Assuming we don’t count the 1966 feature spin-off of the Adam West Batman TV series, Keaton was the first real big-screen Batman, and as such he laid the groundwork for all actors to take on the role since. Here’s why we think Keaton remains the definitive Batman actor.

He prevailed in the face of fan adversity

When Michael Keaton’s casting as Batman was first announced, the actor was best known for his work in comedies including Mr Mom, Johnny Dangerously and most famously Beetlejuice. He had never played an action role, and at 5’9″ with a slender build, he was not the most obvious choice to play the Dark Knight.

Thousands of Batman fans were outraged, and studio Warner Bros was inundated with letters demanding the role be recast. Keaton and director Tim Burton were not deterred by this – and once the movie arrived, most of those fans realised just how wrong they’d been.

He approached the role seriously

For many years, any mention of Batman immediately evoked the memory of the 60s live action take on the character with Adam West. This ultra-camp interpretation of Bob Kane and Bill Finger’s comic book creation was so well-known, that for many years no one thought the character could be done any other way. (Pierce Brosnan, who was considered for 1989’s Batman before Michael Keaton, has admitted he declined the role over fears that it would again be camp.)

However, Keaton – again, hand in hand with director Tim Burton – recognised the potential of playing Batman straight, as in the earlier comic books, and the more mature graphic novels of the 80s (most famously Batman: Year One, The Killing Joke and The Dark Knight Returns).

He embraced the character’s emotional detachment

There’s one key thing about Batman that is frequently overlooked, but really cries out to be addressed: he’s clearly a very strange guy. Going out to fight crime vigilante-style is one thing; doing so dressed as a bat is quite another. Clearly this is not the behaviour of a well-adjusted human being – and Keaton seems to understand this better than any other Batman actor.

Both in the cape, and as Bruce Wayne, Keaton plays up the socially awkward, emotionally distant nature of the character, never going anywhere near the rage and melodramatic excess of some of his successors. (Except, that is, for the uncharacteristically loud “Do you wanna get nuts?” moment.)

He introduced the ‘Batman voice’

Keaton’s performance as Batman contains an innovation which seems so simple, it’s hard to believe no one thought of it before: he uses a different, lower tone of voice for Batman than he does for Bruce Wayne. Adam West never bothered to do this, and Keaton quite reasonably argued that anyone who heard him speak would easily recognise his voice unless he disguised it.

With the exception of George Clooney (who probably realised nothing could have saved him), every subsequent Bat-actor has taken a similar approach. Infamously, Christian Bale affected an extreme growl as Batman, whilst Ben Affleck’s voice was digitally manipulated.

He coined the phrase “I’m Batman”

Another of Michael Keaton’s key innovations in his portrayal of Batman seems deceptively simple, but has come to utterly define the character. In his first scene, the script called for Batman to tell a criminal, “tell your friends, tell all your friends, I am the night.” However, Keaton felt this line was too waffly, and suggested instead he simply declare, “I’m Batman.”

This quickly became an iconic moment, and every Batman actor since has delivered this line at least once. (In a cameo on The Big Bang Theory, Adam West dryly remarked, “I never had to say ‘I’m Batman.’ I showed up, people knew I was Batman.”)

He made Bruce Wayne a more anonymous figure

One of the key complaints of the naysayers when Keaton was cast as Batman was that he was nothing like the handsome, square-jawed, musclebound tough guy that fans felt Batman should be. Every Batman actor since has been closer to that old-fashioned hero ideal, most notably Bale and Affleck, who both piled on the muscle for the role.

However, the fact that Keaton is physically slighter and not quite so conventionally handsome (no offence, Mike) means that he blends into the background more as Bruce Wayne. This is an advantage; while Wayne’s name is famous, the man himself craves anonymity, and the fact that he doesn’t look like he could be Batman out of his suit should help keep his enemies off the scent.

He wasn’t worried about being upstaged by the villains

A lot of leading man actors hate the idea of anyone else stealing their spotlight. Keaton, however, went into Batman knowing he didn’t have any choice in the matter, as he was appearing alongside two-time Oscar winner and larger-than-life actor Jack Nicholson, who took top billing as the Joker, and commanded the audience’s full attention in all his scenes. Happily, Keaton never tried to out-perform Nicholson, allowing his far more famous co-star to take centre stage.

The actor was similarly humble alongside the more flamboyant, scene-stealing performances of both Danny DeVito as the Penguin and Michelle Pfeiffer as Catwoman in sequel Batman Returns.

His performance had a subtle sense of humour

As much as Keaton approached the role more seriously than was the norm at the time, he understood there had to be a balance. His performance as both Batman and Bruce Wayne brings an occasional light touch and gentle humorous flourishes that make the character that bit more relatable and endearing.

This can’t always be said for the Batman actors who’ve come since, with Bale and Affleck in particularly seeming to take things a bit too seriously at times, even when the films went in fairly absurd directions (cough *Martha* ahem).

He wore the best Bat-suit

Opinions may vary on this subject, but let us declare once and for all that no Bat-suit looks as good as the one Michael Keaton wore in the original 1989 Batman. In the initial sequels, the suits got too brash and colourful; in the Dark Knight trilogy, Bale’s suit was all a bit utilitarian; and Affleck’s looked more like a space suit at times. (Based on early glimpses, the suit Robert Pattinson wears in the upcoming The Batman just looks a bit strange and primitive.)

Keaton’s suit, designed by Bob Ringwood, gives us the best balance of the classic comic book look, with at least a hint of real world practicality. Keaton may have gotten some stick for wearing a suit with built-in muscles rather than putting on muscle for real, but body armour has been a key element of every subsequent Bat-suit.

He was smart enough to quit before Batman Forever

Keaton was asked to play Batman a third time in Batman Forever, but studio Warner Bros were pushing for things to be taken in a more upbeat, family friendly direction. Being less than enthusiastic about this approach and unimpressed with the script, Keaton turned down the film (and reportedly a huge payday with it), clearing the way for Val Kilmer to take over.

Most fans agree Keaton made the right choice, as Batman Forever and its even more notorious follow-up Batman & Robin went some way to undoing the good work the first two Batman movies had done. Keaton’s early departure reflected his respect for the character – and the fact that he has decided to return for The Flash would seem to bode well for the quality of the material he’s been given this time around.