Rib Ultra Wire, chartreuse, small (brassy also works) (1 length)
Body Chartreuse Crystal Flash (black, green, gold or silver all work) (5-6 strands, approx. 6in)
Thorax Hareline Quick Descent dubbing, light olive (approx. 4in on the thread)
Hackle European grouse (hen back also fine) (1 feather, 2.5 turns)
How to tie it
Mount an Allen S402BL - if you are fishing for steelhead, use a hook with real strength. And lay a base of black 8/0 thread. Tim ties this in a 10, from 8 down to 14.
Tie in chartreuse small Ultra Wire a couple of millimetres back from the eye and lay a short base over it.
Cut five or six strands of Crystal Flash about six inches long, level the tips, and tie them in by the tips at the same point as the wire.
Bind the Crystal Flash down the shank to the rear. DeFrank takes his round the bend; Tim stops at the rear of the shank and has never found much difference. Return the thread to the front.
Wind the Crystal Flash forward as the body. It is forgiving stuff, any high or low spots in your thread base fill in as you wrap. Two wraps at the eye are enough to lock it off.
Bring the wire forward in the reverse direction. Counter-wrapping it. That is deliberate: if the Crystal Flash gets cut or bitten anywhere along the body, the wire running the other way stops it unravelling.
Carry the wire on to the eye and back again to build a little extra weight at the front. This fly carries no bead, so the wire at the head is where the weight comes from. Lock the wire in and twist it off.
Dub about four inches of Hareline Quick Descent onto the thread and wrap it up towards the eye, then back again to build a solid thorax base. Quick Descent has aluminium in it, so it adds weight as well as bulk, and it dubs very easily.
Prepare a European grouse feather by stripping all the fluff from the base, then hold it by the tip and stroke the side fibres back. It is fragile. A little tearing is fine.
Tie the feather in tip first with about three wraps, lift the tips and trim them out, then take an extra wrap or two to force the fibres rearwards.
Wind about two and a half turns of grouse, no more, stroking the fibres back as you go. The built-up thorax underneath pushes the fibres out away from the body so they can breathe and undulate in the water. That is the characteristic of DeFrank's fly worth preserving.
Bring the thread through and take a couple of wraps to secure. Rather than snipping straight away, pull everything back and stroke the fibres rearwards first, then trim and whip finish.