The pairing of Spencer Tracy and Katharine Hepburn is hugely famous. The same goes for the real-life romance. Since Spence's death in 1967, millions of people have speculated about their relationship, and often over-romanticized it. Hepburn included. And, honestly, there is no clear-cut way to finding out what their relationship was like.

After completing The Philadelphia Story, Hepburn bought the film rights for Woman of the Year in 1941. Hepburn insisted that Tracy star. Unfortunately, Spencer was in Florida, shooting The Yearling and could not sign onto another picture. A week later, a swarm of locusts attacked the cameras, and shooting was brought to a halt.

In the meantime, Hepburn had sold Woman of the Year to Louis B. Mayer, the head of MGM. And upon Spencer's sudden availability, he was signed onto the project. Cukor was Kath's first choice to direct, but George Stevens was hired instead (apparently to help Tracy feel more at ease). Stevens had worked two time previously with Hepburn for Alice Adams and Quality Street.

A few weeks before shooting was scheduled to begin, Hepburn was wandering around the MGM lot, hoping to catch a glimpse of her favourite actor. She finally got one.

Tracy was out for a stroll with Joseph L. Mankiewicz, the film's producer, and Hepburn eagerly approached them.

"Oh, I hope I won't be too tall for you, Mr. Tracy!" She gushed.

"Don't worry, baby." Mankiewicz (not Tracy, as the legend says) replied, "I'm sure he'll cut down you to size."

Afterwords, Hepburn was eager to hear what Tracy thought of her. She went to see Mankiewicz.

"He said: 'Kate Hepburn sure has dirty fingernails'." Mankiewicz told her.

So began the love affair.

Shortly after shooting ended on Woman of the Year, there was certainly an affair going in full swing, but as Tracy was known for being a womanizer, and Hepburn disliked being tied down, it ended shortly thereafter, and Hepburn set about caring for the needy Tracy instead, in order to help fulfill her need to play caretaker.

It has been said that Hepburn wanted to marry Tracy (which is a bit confusing, as it is totally out of character for Hepburn), and he was not totally against the idea, but at the time (mid-40's) his children were too young. By the time they were older, Hepburn no longer had any interest.

Hepburn and Tracy never lived together. If they were working on a picture, they stay is different houses, and never ever were they photographed together. When he wasn't busy shooting pictures, he lived in a bungalow on George Cukor's estate (from 1952 onwards), and Hepburn visited him on a somewhat semi-regular basis.

They also attended George Cukor's famous Sunday afternoon dinners together, in the company of many people, such as Vivien Leigh and Fanny Brice.

Here is an probably over dramatized version of a conversation during said dinner parties, from Garson Kanin's book Tracy & Hepburn:

"I'd have quit the the stage completely," said Spencer, "if it hadn't been for George M. Cohan. I was sort of chunky and funny-looking. I knew I was good, but I couldn't seem to get anywhere. The parts just weren't coming up. Then I got this bit in a show by Cohan. My hero. Selena Royle got it for me. Chester Morris was it in, and Hale Hamilton. Selena......."

He stopped and returned to the present.

"Tell them the rest of it, Spence." said Kate.

"No."

"The thing that made the whole difference. The turning point."

"No."

"Why not?" She said, exasperated.

"Because, you cluck," he shouted, "it's not the kind of thing you can tell people about yourself!"

She made him bike ride everyday. She also made vats of coffee in the beginning to help ween him off alcohol. She quit smoking in order to get him. She also forced him to drink a lot of milk, take long walks, go swimming, and so on and so forth.

In 1962 she stopped making pictures, supposedly in order to give her full attention to caring for Tracy, but instead she did a fair amount of traveling for various Shakespeare plays. It has also been reported that she stalked him on his movie sets and sat behind the cameras knitting. This seems somewhat unlikely, but is entirely possible.

In 1967, the doctor's proclaimed that Tracy was in excellent health, and that he was certainly capable of making a movie. Despite this clean bill of health, Hepburn insisted that Tracy only work in the morning, and even then only for a few hours at a time. So they shot Guess Who's Coming to Dinner, and two weeks after it wrapped, Tracy was found dead in his house on George Cukor's estate, slumped over on the kitchen table with a glass of milk next to him.

They made nine pictures together.