'How do you begin a new era of a popular TV show when it has just seen arguably its most popular lead actor go?'

That was the question Steven Moffat was faced with for The Eleventh Hour. You would think it would be a challenge to introduce not only a new Doctor and companion in a single episode but an entirely new era too. Yet Moffat does it effortlessly.

The plot is relatively straightforward compared to previous Doctor Who stories (and of course the majority of Steven Moffat's future ones) but with so many new elements to the series to introduce, it had to be. The most complicated it gets is The Doctor (Matt Smith) meeting Amy (Karen Gillan) first as a child, returning 12 years later and eventually picking her up as a companion two years after that. Otherwise, the plot is basically an alien convict resembling a snake has escaped from a crack in Amy's wall and intergalactic police the Atraxi (think a giant eyeball and you're correct) are prepared to incinerate the Earth if they don't find him. In order to blend in, Prisoner Zero takes on the form of various coma patients however Amy's boyfriend Rory (Arthur Darvill) is a nurse at the local hospital and alerts the Doctor and Amy about it. This is probably the most simplistic a Moffat story gets and it helps considerably to introduce this new Doctor and companion.

This is such a great introduction story to a new era that arguably it's as good as the excellent Rose by Russell T Davies - and believe me, to have as good an introduction as Rose is going something. It feels like we've always known Matt Smith and Karen Gillan as the Doctor and Amy; both or them slip into their parts immediately.

Matt Smith is so good, in fact, that he has his defining Doctor moment in his very first episode. There's this wonderful scene where the Atraxi shows the Doctor's incarnations in order scanning at the Doctor's request on whether the Earth is protected...and he steps through and says just four words.

'Hello, I'm the Doctor'

Immediately, you know who this Doctor is. It is only beaten in terms of the Matt Smith Era by another moment later on in series 5 known as the 'Pandorica speech'. The thing is, Matt Smith was so great here that I was disappointed when he didn't seem as comfortable in the following episode The Beast Below. In fact, his performance in series 5 never quite reached the heights of how he played the Doctor here. I feel he was better in series 6 and 7 overall but I suppose that's to be expected considering he would have been more comfortable in the part by then.

As for Karen Gillan, she sold me straight away as the feisty Amy Pond. Her no nonsense approach is brilliant, especially when she traps the Doctor's tie in a car door or wracks him over the head with a cricket bat. She quickly became my favourite companion for a while until the excellent Jenna Coleman came along as Oswin/Victorian Clara/Clara.

Oh, and I can't write this review without mentioning Caitlin Blackwood. I'm sure many fellow Whovians will agree with me when I say she is without a doubt the best child actor they have ever had in the show. She's a smart casting choice, looking exactly like a young Karen Gillan (helps that they are cousins, of course) and also coming across incredibly believable in the part to the point where you wouldn't mind if she ended up playing the new companion rather than Karen Gillan.

Overall, The Eleventh Hour is exactly how to do an era introduction story with fantastic acting from the new stars of the show and a brilliant simplistic plot from Steven Moffat that was just what this episode needed.