An unsuspecting commuter was dismayed after stepping on a Mitcham-bound bus that got lost and arrived on alien planet under threat from a swarm of flying invertebrates.

Fortunately the 450-year-old man known as “the Doctor” appeared more than up to the task of navigating his way back to the borough.

The number 200 bus from Raynes Park to Mitcham is the unlikely replacement to the Tardis in the latest episode on Doctor Who, to be screened this weekend on BBC One.

But the presence of the Merton bus has sparked online debate and outcry from transport fanatics, slamming the show’s factual inaccuracy.

A blogger on the site Omnibuses2.0 - reflecting the bus industry in a postmodern world, said: “Of the Easter special, the Radio Times declares it all began with a red London bus. And this London icon to which they refer - a 1981 Bristol VR.

“Correct me if I’m wrong, but no operator in London actually ever bought a Bristol VR new and certainly not London Transport.”

He added: “Why is the BBC describing a Yorkshire bus as from London? Would the programme makers have evoked the same response had it been a Red Wakefield Bus? Or a Yellow Bournemouth Bus?”

A spokesman from the show was unable to comment as it emerged the production crew actually used two identical versions of the incorrect busses to film the episodes in the UK and Dubai.

As for the Doctor, he remained disillusioned over his disrupted journey.

Actor David Tennant said: “The show starts with Michelle Ryan in a catsuit stealing something important. Then she tries to escape on a red bus, a London red bus.

“But London transport being what it is, it slips through a wormhole in time and space and ends up on a planet on the other side of the universe.”

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