No, Pembleton wasn’t cool. His fire burned with white hot intensity. He was great, but cool he wasn’t.
Of those not mentioned yet, Detective Ron “Blood on the Badge” Harris, from Barney Miller, was very cool, except he was part of an ensemble cast so he doesn’t qualify for this thread.
Another vote for Rockford was the coolest though.
Yeah, the rest of the Angels were just eye candy. but “Bree” was way cool.
As was Jamie Sommers - but I think of her more as a secret agent than a detective.
Seconded. I don’t know if it’s what the OP is looking for, but I thought of Lennie when I saw the title.
Most definitely.
Then there was Fox Mulder on The X-Files, who was so nerdy he was cool.
Sherlock Holmes, as played by Jeremy Brett in the Granada series.
DCI Jane Tennison in the Prime Suspect series.
And what, no love for Jack Lord on Hawaii Five-O? “Book 'em, Danno!”
I’m talking 'bout Shaft.
I’m not sure he counts, because technically he isn’t a detective, but Castle is pretty cool.
Poirot by David Suchet (who is always a bad-ass villian in not BBC stuff)
best apartment
best moustaches, (not moustache, plural)
best waddle with the cane
even better than Archie Goodwin (Timothy Hutton)
Yes! I saw him play Iago in an RSC production of Othello in late 1985. He was devilishly good.
No it’s Barneby Jones, no question.
Well he sure had the coolest and best theme tune.
I was going to vote for him - never a hair out of place. But would 5-0 count as an ensemble show?
Leroy Jethro Gibbs. No one else is even close.
Assigning Gibbs spots 1 through 9 on a top 10 list, Robert Urich’s Spenser is number 10. I specify Urich because somebody else played Spenser in a couple of really bad Lifetime movies.
ETA: Avery Brooks’ Hawk would be number two, but he was not a detective, simply because he had Spenser to do the boring detective stuff.
Leroy Jethro Gibbs gets my vote.
Shut yo’ mouth!!
Jim Rockford all the way!
Jim Rockford.
When kidnapped by bad guys, he jammed his foot over the driver’s on the accelerator and the car crashes into a swimming pool.
Rockwood gets out first with a gun and, sitting on the diving board says, “OK, everybody out of the pool.”
They should really make a new Rockford movie.
[hijack]Who would play Jimbo?[/hijack]
James Garner could play Rocky, following the Maverick remake. 
Who is sleazy enough to play Angel?
David Boreanez, obviously. What an incredibly silly question.
You’re in luck. As I discovered in this thread, they’re remaking the series.
Casting it will be tricky.