Watch CHRISTOPHER STEVENS on TV last night: Full speed ahead for this casual celebrity friendship

The great steam adventure

Judge:

Wherever you go this summer, and however you get there, you’re likely to meet groups of celebs doing road shows — and they’ll all claim to be best friends for life.

These couplings are often noticeably forced. Was anyone the least bit shocked when Gino D’Acampo announced last month that he would no longer be touring the world with his ‘bosom friends’ Fred Sirieix and Gordon Ramsay?

But when a natural relationship develops, it doesn’t need exotic locations or expensive set pieces. Former political journalist John Sergeant and actor Peter Davison thoroughly enjoy each other’s company in “The Big Steam Adventure” (ch. 5), and their sense of fun draws us in.

To call it an “adventure” is stretching the term. So far they’ve traveled from Greenwich to Stevenage to Peterborough – all pleasant places, but nothing heart-pounding destinations.

However, there is no doubt about the correctness of the word “steam”. They boarded the Challenge, London’s last working steam tug, slid under Tower Bridge and boarded a 1909 Stanley steam carriage.

At King’s Cross they boarded the Duchess of Sutherland’s steam train before boarding a steam coach called the Puffing Billy for the final, nerve-wracking leg of the first leg to Scotland.

Accompanied by Paul ‘Piglet’ Middleton of the North Yorkshire Moors Railway, they were schoolboys keen for a holiday treat. 79-year-old John beamed every time he was allowed to pull a cable to whistle. He would poop-poop on tugboats and trains, just like Mr. Toad.

Peter pretended to be grumpy, but once he was behind the wheel of the Foden bus, he didn’t want to let anything else take the wheel. The former Doctor Who star boasted of his time in the Tardis and pointed to a quay in the East End: “That’s where I defeated the Daleks, banished them from the earth.” John bit back the question of how many times they had to be banned since .

But he got annoyed when Peter kept pointing out that they should go north and not stop at pubs. “Don’t try to be a compass man,” John suggested. Peter snorted, “I thought he was going to say something rude” – and they all burst into unfeigned laughter.

In the factory

Judge:

Gregg Wallace in Inside The Factory (BBC2) was just as boyishly excited as John. But he always is. “Nothing gets me excited about these programs like pushing a button,” he roared, setting up a machine that made vegan sausages. His cheerful mood faded for a moment when he asked a supervisor if she wanted to watch him on MasterChef. Not only had she never heard of him, but instead she was a fan of the Romanian version. Ah.

However, he quickly recovered and was delighted to discover a guillotine that tested sausage casings to make sure they were not too thin and not too tough. The blade went about its work at a leisurely pace. “Very slow,” Gregg growled. “You would never have decapitated Marie Antoinette like that.

Inside The Factory: Gregg Wallace visits a vegan sausage factory in Yorkshire

It seems unwise for a man with a head like an egg to joke about being decapitated in a vegan food factory. On safer ground, he found himself in the “vertical farm,” a shipping container full of racks of spinach and basil growing under artificial lights.

“It’s where Star Wars meets lettuce,” Gregg explained, before becoming overwhelmed as the LED lights changed color. Shades of purple, red, green and blue mimicked various properties of sunlight.

“Like a disco from the seventies,” he marveled. I bet he would be content just staring at a mirror ball for hours.