The writing is on the wall for Sterling Cooper & Partners, as the agency prepares to close its doors for the final time with this exceptional US drama series coming to an end.

This seventh and final season is awkwardly broken into two parts, with the first seven episodes now available for your boxset-binging pleasure whilst the second half of the season will follow next year.

After his monumental meltdown, Don Draper (Jon Hamm) finds himself still in exile from the agency. It's an uncomfortable situation for him; after all, if he's no longer an ad man, what is he exactly? It's an existential crisis he can well do without quite frankly, considering his dark and mysterious past.

Meanwhile, there's still an agency to run and new creative director Lou Avery (Allan Havey) is tasked with keeping the creative juices flowing. Although seemingly agreeable, he's no mug, as Peggy (Elisabeth Moss) soon discovers after a few clashes with her new boss.

The agency also decides to buy a computer, which makes a number of the creatives disturbingly paranoid.

Elsewhere Pete Campbell (Vincent Kartheiser) actually seems happy out in the west coast office, mainly due to a new love interest; less content is Megan (Jessica Paré) who not only misses Don, but finds that her acting career in LA isn't going as well as she hoped.

There's some good news with Betty (January Jones) at least, who has finally shed the pounds, only to struggle with her relationship with hubby Henry as they clash on political issues.

And then there's Roger (John Slattery), who's still never without a drink in his hand. And if there's one person putting the swinging into the sixties, you can be sure it's Roger.

Saying goodbye can be a difficult thing, but never seeing Don Draper again after this season will take some getting used to. The man men love to hate and that women just love to love is going through a curious period of transition – as is the rest of America on the cusp of a new decade. Despite hitting rock bottom, or maybe because of it, Draper is still the main attraction in Mad Men. No longer the darling of the agency, we see Don like we've never seen him before, vulnerable and broken.

Hamm has created a truly iconic character, and he clearly relishes taking Don on this new journey.

Although Draper has always been the star, there is still a fascinating array of characters in his orbit. Roger for one is still a show-stopper; if ever anyone needed a spin-off show, it would be him.

Some have claimed that the show has gone off the boil in recent years, but the writing – for these seven episodes at least – is as sharp and observant as ever. The series as a whole has been a well-crafted concept that captured not only the mood of a generation, but those who helped shape that mood through the medium of advertising.

It has also produced some fascinating character studies, of which Don Draper is only the tip of a very large agency iceberg.

If you have been drawn into the glamorous world of Sterling Cooper & Partners, the first part of this finale is simply unmissable. Or as the agency showreel may put it, Mad Men: it's been a pleasure.