4. Close Encounters Of The Third Kind (1977)

The Threat: Classic grey alien. These fragile-looking visitors arrive from the planet fairy land in Christmas-bauble ships capable of moving at vast speeds.

The Fallout: Activation of electronic devices, power outages, flapping cat-flaps, shaking fridges, vision implantations... and abducting kids. Pretty low, guys!

The Solution (Nick): “There’s no obvious threat here, unless we start trouble, in which case – self-evidently – the aliens seem more powerful than us.

The clear priorities in such a situation would be exactly as is portrayed in the film: establish a dialogue – though probably not using music, but mathematics, as in the film Contact – and try to find out about their technology.”

5. Independence Day (1996)

The Threat: Their “destroyer” ships measure 15 miles wide, pack nuke-repelling force fields and house a fleet of zippy “attacker” ships that fire “green shit”.

The Fallout: Total destruction. Telepathy reveals their strategy: invade, act all big and bad, milk all resources and zip off to the next planet.

The Solution (Nick): “More total war, I’m afraid, so not much chance of negotiation here. If our computers really were compatible, I guess cyber warfare would seem to be the answer: viruses, trojans, etc.

Alternatively, maybe we could bombard the aliens with offers for replica watches, fake degrees or Viagra, so they’re too busy deleting to destroy us.”

6. Invasion Of The Body Snatchers (1956)

The Threat: They look like us, only they’re not the same. Sprout from “seeds drifting through space for years”. Powers are minimal. But their stealth – that’s scary.

The Fallout: The Poddies organise to “turn” the rest of humanity. Even a baby gets got in a way creepy scene. Paranoia escalates before the Pod-packers’ inexorable, inescapable forward march.

The Solution (Nick): “Speed is of the essence, when faced with an exponential increase in the infection. If you don’t nip it in the bud – or pod – we’re finished. So I’m afraid this is a case of attacking the infected area with fuel-air explosives or nuclear weapons.”

7. The Faculty (1998)

The Threat: Initially, they look like teachers. In alien form, they range from icky fishy-slugs to tendril-dripping monsters. Entry into human bodies begins at the earlobe.

The Fallout: Paranoia and conflict run rampant in high school. Teachers receive multiple hues of makeover. Total takeover by ear inspection follows.

The Solution (Nick): “I think cotton buds might be the key here, despite the ‘Do not insert into the ear’ warnings. Either that, eardrops or a syringe.”