Like a child, I'd hoped for something spectacular and shocking  in Mad Men's (Sky Atlantic) season finale. I should have known such a thing wouldn't happen, just as I'd hoped never to succumb to the American habit of calling a series a 'season'. In both cases, it was a futile wish.

Even though Mad Men has been too elegant, subtle and realistic for wild plot twists and gasping revelations, this didn't stop the fans from chattering and tweeting about possible fantastic endings for Don Draper. My favourite, simply because it was the most ridiculous, was that Don would turn out to be DB Cooper, a man who hijacked a plane in Seattle in the 70s, demanded a wad of cash and some parachutes, and then jumped, vanishing forever in the vast Oregon forests. Now that's what you call a story, and that would have been spectacular, but would have had no bearing in reality at all, and we must remember this is Mad Men we're dealing with, not Emmerdale.

So there were no wild stories, just a neat, low-key series of endings for each of the characters, almost as though the director and his team had been ticking the names off a checklist, hoping to rush through them so they could clock off early and get home before the rain starts.

Betty's story continued on its sad trajectory and our last sight of her came as she sat in her dim kitchen, weary and flat, a cigarette in her hand. This seemed like a clumsy slap on the wrists to all you naughty audience members who smoke, and was a rare example of Mad Men's sleek subtlety being thrown aside.

Peggy's story was brought to an unexpected, though very sweet and warm, conclusion: she found out, in the midst of a phone call, they she loved Stan and so he ran to her office and they kissed. All very nice but it felt rushed, and part of the director's box-ticking, clock-watching spree.

Don's story wasn't rushed. On the contrary, it often felt frustratingly slow, but this was a deliberate effect, underscored by the fact he was literally unable to leave the hippy commune as the place was too isolated. Without his car he was stranded there. So how would our smooth, dapper hero endure, stuck in this sunny, breezy place of enlightenment and peace? How long before he cracks and goes out hunting for booze and broads? That didn't happen. Instead, he became tender and sympathetic, hugging someone at the weird hippy support group who was weeping hysterically. This was a beautiful scene, as the two men clung to one another and not a word was spoken.

This was a new Don, one of understanding and empathy and serenity. Abandoning all subtlety - again - we saw him mediate on a cliff top, ommmmm-ing to the hippy chants in the sunlight and then his mouth twitched into a tiny, satisfied smile.

Oh joy! Don has found peace at last, and he's found it by dropping out of consumer society, the society he did so much to forge and flame. Now that was indeed an unexpected ending, even more so than the DB Cooper hijack theory would have been!

But, perhaps not. The episode ends with the famous Coca Cola advert ('I'd like to teach the world to sing….') and so the heavy implication is that Don took all his hippy enlightenment and went scooting right back to Madison Avenue with it, back in the humble service of capitalism.

Some may say that was a disappointing ending. Don didn't learn anything, did he, if he takes his experiences as a drop-out and just slips straight back in, but I choose to think the tiny smile means he has finally accepted who he is: a man who likes the glamour of Manhattan, and the money and women it brings, and is finally OK with himself. Good on you, Don.