'I'm still me.' These were the words legions of distraught Doctor Who fans had been longing to hear last night. They need not have worried. Despite going to the brink of an epoch-ending regeneration, David Tennant remains the tenant of the Tardis.

What is more, an estimated 10 million viewers were treated to a naked Doctor, too, albeit only for a few seconds. There were also paradoxes aplenty, and brief appearances for many of the Time Lord's former sidekicks and traditional accessories, from the Sonic Screwdriver to K-9, the dog robot.

Russell T Davies's last series finale, before he steps aside for writer Steven Moffat, had been heralded by frenzied speculation among fans that its title, 'Journey's End', spelt the end for Tennant in the role. But Davies was to deliver a rather different 'reality time bomb'. The current Doctor will go on, at least for now, though many of the rumoured twists to the plot were proved correct last night. There were indeed two Doctors on screen for a while and Catherine Tate's Donna Noble ('I'm only a temp from Chiswick') really did become something of a female Time Lord, for a short time. The keys to the story, as some aficionados had suspected, were the Doctor's severed hand and that recurrent pulsing drum beat from previous episodes. Suffice to say a 'temporal prism' and a 'timelock' were both involved, and Davros and his evil Daleks were defeated.

'I was really relieved,' said eight-year-old Lucas Danson, from London, after last night's episode. 'It was very exciting, but I really didn't want him to regenerate into another doctor.'

Ellis Stagg-Neal, aged nine, said: 'It was more exciting than I was expecting. I didn't expect the doctor to stay the same when he regenerated. It was a cliffhanger because we still don't know who his next assistant will be.'

Tennant took over the role of the Doctor from Christopher Eccleston just one series into the triumphant return of the 40-year-old cult sci-fi show in 2005. Tennant had, in fact, been Davies's original choice for the part and in his hands the appeal of the show has gone through the roof - with episodes regularly attracting eight million fans.

Speculation about last night's series finale started last year when Tate let slip that the current series might be Tennant's last when speaking on Jonathan Ross's Saturday morning show on BBC Radio 2.

Tennant countered by announcing: 'I'm doing four more specials and beyond that no one's asked me to make any decisions - and I'm quite happy to be enigmatic for as long as possible.' His claim was supported by reports that he was negotiating to appear in another three series for a salary of more than £1m.

Chat-room sleuths on the internet debated the clues in the text with intensity. The significance of the Doctor's spare hand, stored in a jar in the Tardis, was clear to some.

'As Chekhov said: "If you fire the gun in Act 3, it must be seen in Act 1",' pointed out one fan seriously. 'Which episode of Star Trek does that Chekhov quote come from?' responded another facetiously.

Few leading British actors have not been put in the frame for the role of the next Doctor, at some point including David Walliams, Rhys Ifans, James Nesbitt and Alan Davies. David Morrissey was the bookies' favourite as the episode began. Certainly Morrissey is featured in the trailer for the Christmas special.

Some sources suggest the Time Lord will regenerate in the next Christmas special. In theory, Time Lords can only regenerate 12 times, making any new face the penultimate doctor. The limit is said to have been imposed to prevent them becoming corrupt immortals.

Happily, though, this issue is believed to have been resolved with some fancy metaphysics in a previous series.

Speculation about the destiny of Tennant's Doctor is bound to continue. Although as Tate's Donna Noble noted last night, before returning to her humdrum life in Chiswick, 'There's no such thing as destiny, is there?'

Review: 'Now that Davros is dead, I'm happy'

'A lot of people were looking forward to this. In my school one of my friends said it would be absolutely immense. And he was right. But why are Daleks so evil? They almost destroyed the whole universe. I really don't like Davros (pictured) because he is very selfish. He is trying to take over the universe and that can't be right. Everyone should keep to themselves, that includes the Daleks. Now that Davros is pretty much dead, I am happy.

'There wasn't a boring moment in the episode. It looked exciting from the beginning. At times there was too much happening at once. I thought the Doctor would come back to become his old form, as the tenth doctor, but I didn't think there would be two of him at once. It was quite strange that Donna became a Time Lord too. She's usually daft. But then I suppose she was daft again at the end. I thought it was quite frightening because it looked like it would be the end of the universe.'
Review by Rufus Punt, aged 9

Source: The Guardian 6th July 2008