- "Know what I like most about boomerangs, Lyla? They're proof that things can come back to haunt you."
- —Digger Harkness[src]
A boomerang is a throwing weapon, notably used by Digger Harkness and Owen Mercer. Harkness' variety was designed and supplied by Klaus Markos. It is a steel-made curved blade, sharpened on both sides and perforated by four prolongated holes. A boomerang, as thrown, spins about an axis that is perpendicular to its flight direction and is designed to return to the thrower.
History[]
Used by Digger Harkness[]

Digger Harkness, the original Captain Boomerang.
Digger Harkness threw a boomerang above a man's head, later identified as A.R.G.U.S. agent Kai Wu, letting it to return and stab the victim in the back.[1]
Harkness used his boomerangs in his assault on A.R.G.U.S. offices for killing or injuring many security men and agents. He either threw the boomerangs towards the victims or used them as curved knives for slashing in hand-to-hand combats. Harkness later used one explosive boomerang with small charge during his fight against the Arrow in a train station.[2]
Used by Owen Mercer[]

The new Captain Boomerang against the Flash.
At the behest of Red Death, Owen Mercer used his boomerangs to steal the battery from a Roemer Accelerator of Kord Industries, before being confronted by the Flash and using another boomerang to teleport himself to another place. He later used his boomerang to rescue the new Fiddler and fight against Goldface.[3][4][5]
Possible future[]
In the future Nora West-Allen is from, at some point in or before 2032, one of Digger's boomerangs was put on display in the Flash Museum's Hall of Villains.[6]
Weapon specifications[]
- "Rad! These are a bit more teched out than the one you guys brought to Central City. 3D printed polymer with a circuitry weave."
"Some of Harkness' boomerangs exploded."
"Oh, yeah, there are grooves in here that could definitely pack a C4 charge." - —Cisco Ramon and Roy Harper[src]
- Durability: The wings of the boomerang are theorized to be made of some sort of composite or high-density plastic reinforced with carbon fiber. There is also a collapsible node design.
- Curved blade: Sharpened from both sides with four prolongated holes in the boomerang's body.
- Optional: 3D-printed polymeric explosive boomerangs with sockets for C4 charges.
- Six boomerangs: Are worn on the front side of the jacket beneath the cloak of Harkness and at least two more somewhere else.
- Explosion inducement: Owen Mercer's boomerangs are capable of generating powerful energy based explosions.[3]
- Force-field generation: Mercer can use his boomerangs to generate strong shields of energy to protect himself from harm.[3]
- Teleportation: Mercer can use his boomerangs to teleport by pressing a button on the boomerang that surrounds him in a red light that makes him disappear.[3]
Known users[]
Known victims[]
- Kai Wu, A.R.G.U.S. agent - killed
- Lyla Michaels, A.R.G.U.S. agent - seriously injured
- A.R.G.U.S. agents - killed or seriously injured
Appearances[]
Arrow[]
Season 3[]
Season 5[]
- "Lian Yu"
Season 7[]
The Flash[]
Season 1[]
- "Flash vs. Arrow"
- "Fallout" (mentioned)
Season 5[]
- "The Death of Vibe" (mentioned)
Season 9[]
Comics[]
The Flash: Season Zero[]
- "Fish Fry"
- "Blood Loss"
- "A Little Help from Some Friends"
- "The Impossible Mission"
- "A Minor Setback"
- "A New Home"