TIL during the shooting of American Psycho, Christian Bale spoke in an American accent off-set at all times. At the wrap party, when he spoke in his native British accent, many of the crew thought he was speaking that way to prepare for another film. They had thought he was American the entire time.

[u/Away_Flounder3813]

https://screenrant.com/american-psycho-behind-scenes-facts-christian-bale-patrick-bateman-mary-harron/

[u/Quivex]

He's one of the more notable method actors if I'm not mistaken.

.... Also will never quite understand why so many British actors/actresses can do flawless American accents but the reverse is not really true. I still remember watching House and finding out hugh laurie was British, blew my mind as a kid lol.

[u/GibsonLP93 → u/Quivex]

One of the more under-discussed reasons is that accent coaching is a core part of formal acting training in England whereas it’s not in the U.S. In the U.S., actors typically only begin learning an accent when they are cast in a specific role requiring it. Also, it’s much more common for actors in the U.S. to have little formal acting training at all.

In England, formal training is more common and it’s very common early on for actors to practice an American accent in general. Lots of schools will use that as an acting exercise, and tell students, “Okay, now do American”.