With the nation still recovering from the ‘Bodyguard’ finale, talk has already turned to series two.

A peak of 11 million of us tuned into the thrilling final instalment on Sunday night, and the drama’s creator Jed Mercurio has teased that as many as four series of the BBC drama could be in the pipeline.

But if that does actually happen, there are a few things Jed needs to attend to when he sits down to write the new episodes, according to two people who know their stuff.

In an interview on Monday’s ‘This Morning’, Tony Blair’s former Head of Protection, Frank Armstrong, highlighted three areas that were maybe a little too far-fetched.

First up is David Budd’s [Richard Madden] PTSD, which Frank believes is a major problem when it comes to accuracy.

“To be a protection officer, and certainly in such an important, key position, there’s a very high level of vetting, all the checks are made,” he said. “I don’t think he would have passed muster, he’d have been out early on.”

And as for David’s romance with the Home Secretary Julia Montague, Frank isn’t having any of it.

He said: “If that [the romance] did happen, he would be off protection duties, having that relationship with the Home Secretary.”

Well it definitely did happen, but she’s brown bread, so let’s just forget it ever happened, ok Frank?

But that’s not all that’s bothering Frank.

“Having the illegal firearm in his possession. We don’t always have stashed firearms in parts of our homes,” he explained.

We think Frank’s nitpicking, but he still managed to enjoy the series.

He added: “I thought it was great entertainment. Loads of people asking me if it’s really like this. It’s not as exciting as David Budd’s role.”

Meanwhile, former Home Secretary Alan Johnson was also on the ‘This Morning’ sofa, and he also had some queries about the series’ factual basis.

“There was one that was glaring, very early on.” he said. “David Budd is in the restaurant with somebody else while the Home Secretary was having a very intimate dinner. There are the two coppers plonked down at a table not eating or drinking anything. That wouldn’t happen – big signals are going off: we are bodyguards. What they do is blend into the background, they’re there looking like two other diners, of course they have to order food.”

‘This Morning’ airs weekdays at 10.30am on ITV.