By Don Kaye

Special to MSN Movies

Spoiler alert, just in case the show is still sitting on your DVR: When we last left the 11th Doctor (Matt Smith) at the end of the sixth season of the modern “Doctor Who,” the Time Lord had fooled his enemies – the history-manipulating​ Silence – into thinking he was dead, at least for the time being, while admitting that he had gotten “too big” and was prepared to slip back into the “shadows” for a while. Perhaps, like James Bond – who is celebrating his 50th anniversary in 2012 as a big screen hero, just one year ahead of the Doctor’s own 50th on the small screen – the Doctor has realized that he can work much more effectively if less people know who he is.

That may be a difficult task, because the Doctor’s popularity has grown to new heights over the past few years. While the original incarnation of the show – which started all the way back in 1963 on the BBC, where it ran until 1989 – was nothing more than a cult oddity in the U.S., glimpsed fleetingly on PBS stations, the modern version launched in 2005 has become more popular than ever both in its native U.K. and here in the States, where it is one of the crown jewels of the BBC America cable channel (“Who” panels at the annual Comic-Con are regularly jam-packed).

Bing: More about 'Doctor Who' | More about BBC America

With the premiere of the seventh season finally set for this Saturday (Sept. 1) after being kept a mystery for quite a while, anticipation for the Doctor’s next set of adventures is reaching new heights. The show actually appeared on the cover of a recent issue of Entertainment Weekly, surprising for a cable series with ratings that, while impressive, are still relatively small compared to major network series. The other huge buzz happening around the new season (which will air its first five episodes this fall, with the rest coming in 2013) is a significant change in the regular cast: The Doctor’s husband-and-wife companions, Amy Pond (Karen Gillan) and Rory Williams (Arthur Darvill), will exit the show in the fifth episode, titled “The Angels Take Manhattan.”

Related: 'Doctor Who' gets season premiere date

Cast changes are nothing new for “Who,” of course: The ancient Doctor himself changes bodies every few years – that is, a new actor takes over the role when the current one decides he’s had enough. When the hugely popular David Tennant left as the 10th Doctor in 2009, fans wondered how the show would survive this time, but Matt Smith has proved to be a worthy successor. When Amy and Rory say farewell – in what is being billed as a “heartbreaking” story that takes place in Manhattan (a first for the series) and features the frightening Weeping Angels – they will be followed by a new companion, played by Jenna-Louise Coleman, who will make her debut in the 2012 Christmas Special.

Fans have loved Amy – the spunky, red-headed Scot has been more than up to the task of following the madcap Doctor – but have been less enamored with her somewhat passive yet good-hearted and ultimately courageous hubby. Two of the Doctor’s last three companions before them, Rose (Billie Piper) and Martha (Freema Agyeman), had unresolved romantic feelings for the Doctor, which gave the new series a fresh emotional underpinning (Catherine Tate as Donna, Tennant’s final companion before he left, had a strictly platonic view of the Time Lord). Although it seemed Amy might head in the same direction as Rose and Martha, the rise of Rory threw a wrench in the works, although any hints of a romantic “triangle,” as far as it could go, were more or less downplayed.

What path will the new companion (rumored to be named Clara) take? Will she, too, develop feelings for the 900-year-old alien who looks like a 29-year-old man? Showrunner Steven Moffat has promised she’ll be different from previous traveling buddies. Meanwhile, the new season will also feature, in its premiere episode, the return of the dreaded robotic race the Daleks – and this time, it will reportedly feature Daleks from across the show’s entire run. That itself may foreshadow 2013, the show’s 50th anniversary, where plans are afoot for some kind of celebratory event. Could all the surviving Doctors – which include Smith/Tennant predecessor Christopher Eccleston, Paul McGann (the eighth Doctor), Sylvester McCoy (the seventh), Colin Baker (the sixth), Peter Davison (the fifth) and the legendary Tom Baker (the fourth and still, with seven seasons, the longest-serving Doctor) -- be assembled for this extraordinary milestone?

We’ve still got a year to go before that happens. In the meantime, “Doctor Who” – the longest running TV series of its kind, and in all of science fiction -- will no doubt keep surprising, scaring and delighting us. All aboard the TARDIS, everyone …