The Intruder is one of my favorite steelhead flies. The fly shown is tied close to Ed Ward‘s original recipe, on the shank of a Mustad 36890, cut off half way around the bend, and straightened. A loop of hard monofilament is tied in at the rear of the fly, and the fly is rigged by running the tippet through the eye of the hook, over the length of the shank and through the loop at the rear. A hook is attached with a non-slip mono loop, and a small piece of soft tubing, through which the leader passes, is used to keep the leader tight on the rear stub of the shank.

Shank- Mustad 36890, cut at bend and straightened
Thread- 6/0
Eyes- various to adjust sink rate
Tag-three turns oval tinsel
Loop- hard monofilament, bent to shape
Butt- three turns chenille
Tail- four to five ostrich flues per side
Butt hacke- dyed silver pheasant tail, spun in loop
Body- as I understand, the Intruder was originally dressed with a chenille body, palmered with a saddle hackle. I most often use diamond braid, as I find the fly fishes just as well, sinks more readily, and casts lighter.
Collar- deer hair or arctic fox, spun in a dubbing loop.
Hackle- ostrich, either two turns of appropriate length, or two turns of ostrich spun in dubbing loop
Wings- hackle tips
Facing hackle- three to four turns schlappen, fronted with two to three turns of dyed guinea hen.
Head- dubbing, spun in loop, to cover base of eyes.

Any number of color combinations can be effective. Some of my favorites are blue/black/purple, orange/olive, pink/white, brown/orange.

Junction tubing on butt of hook to secure and align trailing hook.

The Intruder adapts well to being tied on a tube.