recently I came across a couple scarves I had made several years ago. I had based them on a long, skinny purple scarf that Rogue wore in the first X-Men movie. she seems to have at least two of them, one more sparkly than the other. they both seem to be knitted in a very loose stockinette stitch and allowed to curl.
50-100 grams of dark purple sport to worsted-weight yarn (50g should be enough but if you want the scarf extra long, you may need more.)
knitting needles, much larger than what you would normally use. US 11, 13, or possibly even 15.
cast on about 20 stitches. work in stockinette until the scarf is long enough to wrap around your neck two or three times and reach down to your knees, or however long you want it. bind off.
for the first scarf I made, I only had 50 grams of light worsted wool and cast on 15 stitches. for the second one I had 100 grams of Cascade Pima Tencel color #2493 and cast on 20 stitches.
so far this is the best picture I've found of Rogue wearing the scarf. in the movie it looks more purple.
I might try taking screenshots.
gauge should be nice and loose. keep in mind while you're knitting that it will look much wider than it will end up when you wear it, as the fabric will pull down, curl, and become narrower when it is worn.
the left side is more like how the fabric will look when the scarf is worn; the right side is more like how it looks when you're knitting it.
edited to add screenshots.
it looks like she could have 3 different scarves, the sparkly one, a non-sparkly one, and possibly a mostly non-sparkly one with sparkly sections. or the non-sparkly one has the sparkly sections but they don't show up all the time. the scarf also looks like it would uncurl to be much wider than the ones I made.
closeup of loose stockinette stitches:
very curly edges:
another no-sparkly closeup:
sparkly patches? (see also magazine scan above)