Alfred Pennyworth has become Bruce Wayne’s most trusted ally in Batman’s fight against crime. Of course, it helps that he’s more than just an English butler who can get the smell of Catwoman’s perfume out of a cape and cowl. He also is a father figure — perhaps the only person who can understand how the murder of Bruce Wayne’s parents would drive the young boy to become Batman.

It’s this insight that Michael Caine has emphasized in his portrayal of Alfred in “Batman Begins” and “The Dark Knight,” adding a twist to a character that began, much like comicbooks themselves, as a throwaway.

Alfred was created not for the comicbook but for Columbia Pictures’ 1943 “Batman” serial, apparently to fill two needs: to drive Bruce Wayne around cheap backlot sets, and to serve as comic relief. William Austin — a British subject, like the rest of the big-screen Alfreds to date — maintained the butler’s stiff upper lip even through the practical jokes of Wayne, who surely scared a few years off elderly Alfred’s life by blowing up a vase next to the unsuspecting butler with a radium gun. The Dynamic Duo was still trying to startle Alfred into an early grave as Eric Wilton took over the role for 1949’s sequel serial, “Batman and Robin.”

As the actor cast in the now-classic 1960s TV series, Alan Napier had never heard of Batman and surely had no idea what he was in for. With camp and comedy infusing almost every aspect of the show, Napier turned Alfred into an ideal straight man who took in stride the craziness of using a machine to impersonate Batman’s voice on the phone and driving underage Robin to crimefighting duties.

The 1970s were schizophrenic for Batman fans: The comics became darker, with Alfred developing a past as a combat medic and as a father figure present in Bruce Wayne’s life from a very young age. On TV, Batman mostly ditched his faithful servant to hang out with the Super Friends, Scooby-Doo and Bat-Mite on Saturday morning cartoons.

When Tim Burton brought the comics’ darker version to the screen in 1989, Michael Gough combined the previous versions into a grandfatherly Alfred that was gentle, funny and even a bit subversive. Where previous Alfreds had all fervently bought into Wayne’s crusade, Gough’s advocated a more normal lifestyle. In a controversial scene, Alfred broke the trust placed in him by exposing Batman’s identity to Kim Basinger’s Vicki Vale. The controversy was put to rest with a short onscreen exchange in 1992’s “Batman Returns.”

Gough’s face brought some continuity to the rotating casting in Joel Schumacher’s sequels, rolling with the increasingly campy scripts and heavy-handed father figure imagery of “Batman Forever” and “Batman & Robin.” He also added the role of pitchman, appearing as Alfred in commercials for Diet Coke and OnStar.

Caine’s Alfred, first seen in 2005’s “Batman Begins,” deepens his relationship with Bruce Wayne and is more of a true friend and partner to Batman. Just how far Alfred will willingly go along with Bruce’s crusade remains to be seen. Alfred has traditionally tolerated the Batman persona as long as Bruce remains safe, something Heath Ledger’s Joker is sure to push to the limit in “The Dark Knight.”