4. ET's shoot

The production for ET kicked off in September 1981 under a tight veil of security.

Paranoid that someone would leak the plot and copycat films would flood out, Spielberg insisted that the cast - including Dee Wallace and Henry Thomas - read the script behind closed doors.

The shoot in various chunks of LA was called A Boy's Life to avoid raising suspicion and all those on set had to wear ID badges.

It was a largely smooth production period, switching between a Culver City high school, Laird International Studios in the city and suburban locations in Northridge and Tujunga.

Spielberg shot chronologically (as much as possible, though some shots were later completed at a redwood forest in Northern California), which allowed his young main cast - Thomas as Elliott the lad who befriends ET, Drew Barrymore as his sister Gertie and  Robert McNaughton as brother Michael - to bond with the poo-coloured critter on set.

Another helpful aspect was keeping the puppeteers as far away from the set as possible, so the children could maintain the illusion of working with a "real" alien.

And every adult, save for Dee Wallace, who plays the kids' mother, are only seen from the waist down in the first half of the movie, helping to generate a kids-eye view of events.

Despite the complicated nature of ET, Spielberg was able to finish shooting in 61 days, four days ahead of schedule.

With visual effects and John Williams' iconic score added, the waddling creature was ready to meet cinema audiences.

The movie was previewed in Texas, scoring high marks from viewers and got its official premiere at the closing gala of the 1982 Cannes Film Festival.

And then it opened in America...

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