We rejoin the action as Flash and the Flashettes are under fire from Prince Barin’s rocket ship. They are trapped in a cave with absolutely no way out. We saw them facing down certain death last week, firm, determined expressions on their faces.

"Is there any way out?" asks Flash.

"Yes" replies Aura, "the trap door".

So they open the trap door and escape.

Hurrah!

The final blast from the rocket ship brings down the cave’s roof and all inside (were there anyone inside) would be crushed to atoms. Ming is pleased. Barin – who wasn’t driving the rocket ship after all – is appalled.

Everyone is fine except Vultan – he’s a bit woozy. So they join forces in that way that heroes do and help him from the cave.

As our heroes make their way down a passage they see, coming in the opposite direction, several guards escorting Prince Barin to a dungeon. Zarkov and Aura are surprised…

…as are Flash and Dale. They realise almost immediately that this proves their friend wasn’t driving the rocket ship. They look appalled but inside they’re almost certainly chuffed.

Flash beats up all the guards and rescues Barin. They embrace tamely. Even this mild demonstration of affection chills Zarkov to his very core.

But hold hard! Flash hasn’t done a very good job of knocking out all the guards – this one is still awake and is amazed by what he has just seen. Either the ghosts of the Earth people walk the caves beneath Ming’s palace or they have somehow managed to cheat death.

Back in the lab – surely the last place anyone would think of looking for Flash and Zarkov – they tend to the wounded King of the Hawk Men.

The Tin Man brings news to Ming that Flash lives. Ming is appalled.

The Tin Man and two guards go down to the lab to arrest Flash. Rather charmingly they knock on the door first.

This isn’t damage to the film – Zarkov has rigged up an electric current which runs through the door if unfriendly people are wont to knock on it.

The Tin Man – realising he’s not wearing the right clothes to be messing around with electrical current – is appalled.

Ming arrives to take charge. He orders them to "cut off the power that supplies electric energy to the laboratory". I suppose being emperor of the universe means no one will have the sheer balls to point out that "power", "electric" and "energy" all mean pretty much the same thing.

"We can hold out indefinitely" proclaims Zarkov. Flash grins like a nutter.

Smiles turn to concern when "indefinitely" turns out to mean four seconds. The power is cut off and Zarkov’s box of tricks goes limp.

But wait! An alarm sounds – there is an air attack on the way. It can only mean one thing…

…yay for the King of the Lion Men.

"Gyro ships" exclaims Zarkov as a fleet wobbles and shakes uncontrollably past the camera. A quick internet search suggests that a gyroscope is "used to maintain equilibrium". The Lion Men’s gyro ships were therefore either named by an enemy or someone with a sense of humour (or both).

Ming orders that the lab door be destroyed and the prisoners taken to the throne room. They zap the lock and stride purposefully in. Is it just me or is a fight on the cards?

Sadly not. Zarkov restrains Flash and they go meekly with the guards. Meanwhile, Ming is watching an exciting air battle on his television and invites the prisoners to join him.

Aura the Merciless berates her father for treating her like a common criminal. He replies that she now consorts with enemies so deserves all she gets. Aura is appalled.

The battle rages on TV and it looks as if the Lion Men are winning. Ming is appalled and orders that the prisoners be taken to the tunnel of terror. If he is going to be defeated in battle, they won’t be alive to see it. But wait! The Lion Men of Mongo invade the throne room.

A massive brawl breaks out between… basically everyone we’ve seen over the past twelve long weeks.

Ming runs away.

And does a comedy "which way shall I go?" that totally undermines his credibility as an evil tyrant capable of ruling the universe.

Ming reaches the tunnel of terror and the high priest – who was arrested and imprisoned a few weeks ago but now seems at liberty to once more stand by his gong in case someone asks him to summon the now deceased fire dragon monster – and whispers something in his ear.

Ming then runs down the corridor. His costume wasn’t designed to keep his dignity while running.

There follows a very strange sequence in which dramatic music accompanies Ming climbing onto a small plinth, extending his arms as though addressing several hundred adoring fans, and being sprayed with smoke. All the while, the evil high priest buggers about pulling levers and smirking as though he is doing something thoroughly despicable.

Flash arrives but the high priest explains that Ming has just killed himself. Aura is appalled. Any second now she’ll no doubt realise this makes her empress of the universe and she can start kicking ass.

Zarkov radios Earth to say they are coming home. Suddenly, they inject a note of drama into the episode by telling us there is only "a chance in a million" that the return journey will be successful.

But their entire conversation was over heard by the high priest of Mongo. Oh nuts – I bet he does something evil to them.

I was right – he’s messing about with some of Zarkov’s test tubes. He cackles and then picks up some sort of futuristic egg timer.

Yay! Aura is empress of the universe and has overcome the grief of her father’s demise. She pleads with them to stay with her but Flash is having none of it – he wants to go home and not even a gorgeous brunette who is clearly gagging for it will keep him on Mongo.

But there may yet be a rotten apple in the ointment – the high priest has been doing something nefarious aboard Zarkov’s rocket ship.

They say their goodbyes. It is acceptable to shed a tear at this point.

They wave their friends off.

The rocket ship bursts into flames (in a good way I think) and they are on their way.

As Aura muses openly that Flash and Dale will find happiness back on Earth, the high priest worms his way into their four-shot and says that Flash will only find death. Whatever subtlety may have been in his performance in previous weeks has been tossed away now and he’s in full panto villain mode.

He reveals that he’s put a bomb in their ship. Vultan throttles him but it isn’t enough – there is still a bomb on the ship.

And it is cleverly hidden – he’s put it on a desk amongst a bunch of other things. No one will ever find it there.

Flash gets the radio working just in time to hear Barin’s repeated cries of "Flash – a bomb! A time bomb!" Dale is appalled.

They find the bomb and Flash throws it out of the window. At least the movie serial makers of the 1930s realised it would be quite painful to open a rocket’s window and stick your arm out while in space.

Back on Earth, the newspapers report the happy news.

Zarkov announces that they are about to land but Flash and Dale are too busy making gooey eyes at each other.

Zarkov is app… no wait – he’s smiling in a quite sinister way.

They kiss.

The end.