Intruder
The Intruder is the spey world's flagship - a big translucent profile on a shank-and-trailing-hook chassis, built to swing across steelhead runs and change minds.
Steelhead eat no meal on their spawning run - they attack on instinct - and the Intruder was engineered for exactly that psychology: a large, breathing, see-through silhouette (ostrich, rhea, flash over dumbed shanks) that swims broadside across the current on a spey swing, with a small trailing stinger hook that holds what the profile provokes.
What it imitates
Nothing edible in particular - a squid-prawn-baitfish PRESENCE sized to trigger territorial aggression in anadromous fish.
When & where it wins
Winter and fall steelhead swings, salmon rivers, anywhere two-handed rods sweep runs; the standard modern alternative to classic featherwing speys.
How to fish it
The swing: cast across, mend once, let it swim broadside under tension through the bucket, step down, repeat. The take mid-swing is the entire religion.
Sizes & variants
Tied on 25-40 mm shanks with trailing hooks; black/blue, pink/orange, olive/white by water and mood; weighted or unweighted by tip choice.
Tying notes
Composite stations of ostrich/rhea/flash - the advanced-tying merit badge; commercial ones cost accordingly and last.
Common mistakes
Over-weighting (it should SWIM, not dredge - the sink tip does depth), stripping it like a trout streamer, and losing faith mid-run: swung-fly fishing pays in singles, not volume.