You do mean Karen Allen don’t you?
(Holy cow that lady is smokin’ hot. I don’t know what it is about her. I’ve never seen her in anything else; maybe it was that chemistry. I used to work with a girl who looked exactly like she did in Raiders, just a bit thinner.)
Whoops. Yeah, Karen Allen. Nancy Allen was pretty hot too, mind you.
I completely agree about the Clark/Lex connection on Smallville. Two great tastes that taste great together. Lana Lang is a soulless harridan and should die a painful death. Oh, and Lex Luthor is by far the most interesting character on that show.
Also about House and Wilson, natch. Wilson should move back in and be House’s little homemaker.
Stop reading my mind, people!
Finally we agree on something! Plus, he was cheating on his fiancee, which makes him kind of a dick.
Other examples of good chemistry:
Jennifer Tilly and Gina Gershon in Bound. Hawt.
Josh and Donna on West Wing.
Definitely. A completely dream for this 14-year-old. Though now whenever I see Perlman, I can only imagine Hellboy.
The Good
I third the **Winchester brothers ** from Supernatural. They don’t even need to speak. They convey such emotion - love and fear and absolute commitment all wrapped up into one with with just a prolonged glance between Sammy and Dean…
Pirates of the Carribean
Captain Jack Sparrow has more chemistry with both Wil and Elizabeth than they have with each other, but this is not their fault. The captain just oozes that kind of appeal with everyone - pirates he’s cheated, sea godessess, authority figures trying to kill him etc… He’s just chemistry positive.
The Bad
Spider Man
**Peter ** and MJ. The problem is that I find Kirsten Dunst to be such a bad actor that I can find zero reason for Peter to even be talking to her, much less romantically involved with her. The way she speaks her dialogue at the graveyard scene of the first movie makes me shudder. (Now I feel mean) 
Yeah, I was thinking about his hotness in relation to anyone and definitely NO on him and Drew Barrymore in Music and Lyrics. Cool as pals, but as a couple??
Notting Hill – not so much
Four Weddings and a Funeral – no one could be hot with that stick Andie McDowell
About a Boy – meh
American Dreamz – ew
Love Actually – sweet but not quite right
Maybe he is just better as the wry pal.
Jensen Ackles and Jared Padalecki of Supernatural and Milo Ventimiglia and Adrian Pasdar of Heroes are good friends in real life, and that translates into radiant chemistry on screen. You can tell both pairs just enjoy the hell out of working together.
Heroes is full of duos with great chemistry, but I haven’t seen anyone mention Sylar and Mohinder yet (but I may be blind). When Sylar was pretending to be Zane Taylor, he had this strong vibe of awkward happiness, like he was enjoying someone’s friendship for the first time ever and wasn’t allowing himself to care that he had to pretend to be someone else to do it. It was surprisingly moving. Mohinder became a more dynamic character around Sylar in that part of the storyline, so he benefited from the friendship as well. (And then, of course, came the torturing and trying to kill one another. But after that, who was the first person Sylar called when he was upset? That’s right, Mohinder. And who did he keep ever by his side in the future AU? Uh-huh, his boy Mohinder. nods sagely)
ETA: Another pair with great chemistry was Kyle Secor and Andre Braugher on Homicide: Life on the Street. The way they played off one another in the interrogation room was amazing to watch.
This is what I was coming in here to say. I’m a huge sucker for romantic comedies, and I think this may be the only one at which I was rooting for them NOT to get together (romantically) at the end.
Bad:
Audrey Hepburn and Cary Grant in Charade. I love the movie, love both of them, but Cary gives Audrey absolutely nothing to work with here, and she’s reduced to giving him moon eyes.
Marilyn Monroe and Laurence Oliver in The Prince and the Showgirl. I know he loathed her, but surely one could look at her and give something to the moment. Again, the man is the cold one, since she is at least attempting to act it.
Most of my good ones have already been mentioned.
She probably will. A running joke in our house is that she is such a frequent guest in the Smallville hospital that they’ve named a wing after her. 
We must be close in age. 
Tom Hanks and Audrey Tautou in The Da Vinci Code had no chemistry.
Natalie Portman and Jake Lloyd in The Phantom Menace had majorly faked and very disturbing chemistry.
I was the first to mention Hiro and Ando.
Ewan MacGregor actually had better chemistry with Natalie Portman than she had with Hayden Christiansen. I knew how the story was supposed to go but I kept expecting Obi Wan and Padme to get together.
Thanks to gallows fodder for mentioning Braugher and Secor on Homicide: Life on the Streets. I loved that show. I managed to catch a few minutes of it today on a cable channel at work, but people had to come in and I actually had to work. I forgot how great that show was, Braugher was the standout of the show.
BAD: Jack and Mrs Roper. Mr and Mrs Roper. Jack and Chrissy. Jack and Janet. Janet and Chrissy. Jack and Mr Roper. Jack and that smarmy guy who was supposed to be his best friend. Yes, it was supposed to be a comedy, a work of fiction, even silly, but few things in that show even seemed the least bit likely. Not even for the characters as they were written.
So, why did I watch it for its entire run …?
Also: in the non-romantic category, Mr. Tumnus and Lucy from The Chronicles of Narnia had amazing chemistry. I don’t know how close James McAvoy and Georgie Henley were during filming, but I had no trouble believing that Mr. Tumnus cared, very deeply, about Lucy.
Yes! And also Johnny Depp and the little boy from both Finding Neverland and Charlie and the Chocolate Factory. Similar great adult/kid as “equals” respect and chemistry going on.
I like the goofy chemistry between him and Julia Roberts in Notting Hill, but generally, he is sort of chemistry-less. But the Sandra Bullock thing was probably the worst.
We’re talking about Hugh Grant, yes? I think his best chemistry was with Emma Thompson in Sense and Sensibility. He still had the awkward thing going on, but I did really believe there was something between them. Maybe she just made up for it.
Which, of course, makes me think of Emma Thompson and Anthony Hopkins in The Remains of the Day. Such chemistry! Such passion! Such repression! le sigh.
Good. She can’t suffer enough, in my estimation. In fact, she’s one of the main reasons I stopped watching midway through season three. That and the fact that the slashy goodness kinda declined after season one.
Maybe When I think about it, I was closer to eleven, but that’s still pretty close.
The main reason that I don’t like “romantic comedies” is that I never really get why the two main characters are supposed to like each other. I never thought of it as lack of chemistry, but I guess that’s exactly what it is.
My favorite exception: Adam Sandler and Drew Barrymore in The Wedding Singer. GREAT chemistry.
I thought the chemistry between Sandra Bullock and Benjamin Bratt was pretty good in Miss Congeniality. Between her and Sylvester Stallone in Demolition Man? Not so much.
Ben Stiller and Christine Taylor had such great un-chemistry in Dodgeball. You could just tell that they were having so much fun with their parts.
Great “buddy” chemistry? Turk and J.D. on Scrubs. And Munch and Tutuola on Law & Order: SVU. And of course, Jay and Silent Bob.
And…can we really have gotten this far without mention of Mulder and Scully? Please tell me I missed something!?
I came in to say just that. Spike and Angel were always excellent together. Another one was Spike and Buffy, starting from Spike’s first appearance; not just when he fell in love with her.
Another excellent non-romantic pairing: George Clooney and Brad Pitt in Ocean’s 11 & 12. When they were on screen together, there was more chemistry than when Clooney and Roberts were together.
No love for Tom Hanks and Meg Ryan? I’ve always loved seeing them together in their romantic comedies.