My favourite British accent by an American actor

From Dr Geoff Lindsey.

…and it was in a film with no British characters! PLUS extra mystery accent!

Picture credits
Dominic West by Peabody Awards
https://commons.wikimedia.org/wiki/File:Dominic_West,_May_2004_(6)_(cropped).jpg
Idris Elba by DFID – UK Department for International Development
https://upload.wikimedia.org/wikipedia/commons/8/8f/Actor_Idris_Elba_at_the_%27Defeating_Ebola_in_Sierrra_Leone%27_conference_%2815418119105%29.jpg
Hugh Laurie
https://commons.wikimedia.org/wiki/File:House_logo_new.jpg
Damian Lewis by Sean Reynolds
https://commons.wikimedia.org/wiki/File:Damian_Lewis_and_Helen_McCrory_(8464894420).jpg
Christian Bale by Harald Krichel
https://commons.wikimedia.org/wiki/File:Christian_Bale-7838.jpg
Robert Pattinson by Maximilian Bühn
https://commons.wikimedia.org/wiki/File:Robert_Pattinson_Premiere_of_The_Lost_City_of_Z_at_Zoo_Palast_Berlinale_2017_02.jpg
Andrew Garfield by Sony Pictures
https://en.wikipedia.org/wiki/File:Andrew_Garfield_Spider-Man.jpg
Tom Holland by Gage Skidmore
https://commons.wikimedia.org/wiki/File:Tom_Holland_Spider-Man_statue_(51984714091).jpg
Mille Bobby Brown by Gage Skidmore
https://commons.wikimedia.org/wiki/File:Millie_Bobby_Brown_(41915336280)_(cropped).jpg
Charlie Heaton by Greg2600
https://commons.wikimedia.org/wiki/File:CharlieHeaton2017_(cropped).jpg
Joseph Quinn by France RC – Roster Con
https://commons.wikimedia.org/wiki/File:Joseph_Quinn_en_2022.jpg
Daniel Kaluuya by Universal Pictures
Benoit Blanc by Netflix