Try “The Safecracker” 1958 Ray Milland.
Still trying to find the full movie but have viewed the trailer.
Definite car chase with a SS or MkIV
Cheers Jordy
Graham
Locally, a couple of years ago The Doctor Blake Mysteries had a great opening sequence of a saloon It’s episode 8 of series 3 but sadly most of what is shown on youtube has deleted the opening sequence and is shown mirror imaged , But the car appears in the background briefly near the start
The same car is to appear in this year’s series briefly.
There are some quite nice appearances of the Lady Lyons’ CDU800 in “The Inspector Alleyn Mysteries”.
Peter
Here is very interesting movie database with Mark IV according to the importance in the movie:
http://www.imcdb.org/vehicles.php?resultsStyle=asImages&sortBy=4&make=Jaguar&model=Mk.IV&page=1
You just choose car model and movie list shows up 
Personally the best one for me is Foyle’s War - TV Series
1.5 Litre MK4 :
http://www.imcdb.org/vehicles.php?make=Jaguar&model=1�+Litre&modelMatch=1&modelInclModel=on
2.5 Litre MK4 :
http://www.imcdb.org/vehicles.php?make=Jaguar&model=2�+Litre&modelMatch=1&modelInclModel=on
3.5 Litre MK4 :
http://www.imcdb.org/vehicles.php?make=Jaguar&model=3�+Litre&modelMatch=1&modelInclModel=on
Somehow the war time and SS & Mark IV stick together very well
I like this photo from movie “The Flame and the Lemon” This creates atmosphere…
Wow.
That’s a WAY better response than I ever thought would appear.
Thanks for that.
For the Mark V lover there is the Australian series ‘A Place to Call Home’
Often shows the grandmother being chauffeured around in a silver Mark V.
Same colour as mine 
Don’t believe the accuracy of all the identities in IMDB…
http://www.imcdb.org/vehicle.php?id=204956#Comment2104786
That said, I must admit they changed it very quickly when the error was pointed out.
Peter 
These pics appeared on the pub list. and reminds me of the pic above
Looking at the Foyles war pics , like most movies , it seems that Mk IVs were made earlier than we thought.
I recall various Mk IVs in Foyles series. and in Lunch with Mussolini.
I suppose it’s handy for producers that MK IVs look so pre war.
There was also a polish program " jaguar 1936.
Ed I know this Polish movie " The Jaguar"
It has very interesting plot - the guy buys SS for high price and one hour later sells it for half price …
As for the Blackout headlight covers for Lucas P100L do You know who made them?
I’m looking for one set !
The covers were the originals that came with the car, Being delivered in 1940 covers were mandatory
They wouldn’t be terribly hard to make.
They replace the lens.
Ed, do You know what the covers were made of?
I presume it was steel?
They were just sheet steel , spot welded together , They were a bit complicated in that there was the provision to slide the rectangular glass lens in at the back and the inner section could be tilted [ high and low beam ?}
Although some might say that Mr Lucas was already responsible for black out precautions on UK roads : >)
Attached close up pic