Early police series about a Canadian Mountie seconded to Scotland Yard.
Yes, it's the type of show later parodied by Police Squad/Naked Gun etc., but it more than makes up for it for having copious amounts of shots on the streets of the London of the time (plus a few treks out into the Hertfordshire countryside). Plus I did like how Detective Maguire's new colleague were always so nice to him!
https://archive.org/details/dial.-999.-s/Dial.999.S01E01.The.Killing.Job.avi