Alien: Productions Begins

leading from

Alien

Ridley Scott's creative turnaround

Other directors approached

Greenlighting

Brian Johnson comes aboard Walter Hill drops out as director
Ridley receives the Alien script
Ridley arrives in Hollywood
 Dan O'Bannon leaves his sick bed (see section A)
Seeing Texas Chainsaw Massacre
News of Ridley overturn concerns
Terry Rawlings comes aboard to edit
Into The Necronomicon

Giger tells Mia: "Quit your job, Hollywood just called"
Ridley, Carroll And Giler visit Giger in Switzerland 
Giger flies to london for a meeting at Ridley Scott Associates
Dan the Script Surgeon

Hello Moebius! Goodbye!

Initial casting of Jon Finch as Kane 
 Yaphet Kotto joins Alien

Harry Dean Stanton's Audition  
Ian Holm cast as Ash
Casting Tom Skerrit as Dallas
Veronica Cartwright cast as Lambert 
Helen Mirren auditioned for Ripley

Sigourney Weaver cast as Ripley

Casting John Hurt as Kane