The Alien Legacy (1999) was a "free" bonus disc for purchasers of the 1999 Alien Legacy Box set (first DVD release of Alien movie series). The "free" bonus disc was acquired via a special mail-in coupon included with the Legacy box set.

There is doc. material in this feature exclusive to it (found nowhere else).

1 hr 8 min (68 min)
Aspect ratio: 1.33 : 1

TheDigitalBits.com -- back in 1999 -- said this:

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All in all, this is a good look into the making of the original Alien. The documentary boasts new interviews with Ridley Scott, Ron Cobb, H. R. Giger, Dan O'Bannon and others. It's a bit talking-heady, and could probably have been trimmed. But if you're interested in a behind-the-scenes look, particularly at the production design, then this is well worth a watch. I'm not sure I'd buy the whole set just to get this disc, but I'm sure glad I have it.

The shot-on-video quality is generally very good, intercut with film excerpts and older documentary clips. The audio is in stereo, and sounds fine. There are no extras, no chapters, and no main menu - you simply put the disc in your player, and away it goes. On my DVD screener copy, the subtitles defaulted to on - a minor inconvenience. The disc also arrived in a slip-sleeve, of the type that CD-ROMs are often packaged in.