From STRIKE commander to mercenary
Brock Rumlow leads STRIKE, the elite S.H.I.E.L.D. unit that Steve Rogers works with at the start of Captain America: The Winter Soldier. He is calm, capable and seemingly loyal, the kind of soldier Steve would trust in a firefight. The film makes good use of that trust. When the true nature of S.H.I.E.L.D. comes to light, Rumlow is revealed as one of the people who were never on Steve's side.
By the time he returns, he has a mask, armored gauntlets and a new name. Crossbones is a hired gun with a personal grudge, which makes him more dangerous than the faceless soldiers he once commanded.
Every Rumlow appearance in order
- Captain America: The Winter Soldier (film, essential)
- Captain America: Civil War (film, essential)
- Avengers: Endgame (film, essential)
- What If...? (series, optional, voice role)
All three films are essential on our timeline, but for reasons bigger than Rumlow. In each he is a supporting villain whose moments matter to the plot.
Key scenes without big spoilers
His standout moment in The Winter Soldier is the elevator fight, one of the most praised action scenes in the whole franchise. Steve steps into a crowded lift with Rumlow and his team, and the tension builds quietly before it explodes.
Captain America: Civil War opens with Crossbones leading a raid in Lagos, chased by Steve, Natasha, Sam and Wanda. That sequence sets the entire movie in motion, since what happens there fuels the push to put the Avengers under government control.
Avengers: Endgame brings him back for a quick, clever callback to the events of the first Avengers film. Fans who remember the elevator scene will catch the joke. In What If...? he turns up, in voice form, in one of the animated alternate timelines that remix familiar MCU events.
Who he is tied to
Captain America (Steve Rogers) is his main enemy, and their rivalry is personal because the two once fought side by side. Black Widow (Natasha Romanoff) and Falcon / Captain America (Sam Wilson) are part of both of his big film fights. Winter Soldier (Bucky Barnes) is the other link: Rumlow is part of the HYDRA operation that keeps Bucky under control, and in Civil War he deliberately uses Bucky's name to get under Steve's skin.
Frank Grillo as Crossbones
Frank Grillo gives Rumlow a grounded, physical menace. He looks and moves like a real soldier, which sells both his early loyalty and his later turn. Even with a mask on in Civil War, his voice and body language make the character easy to read.
Grillo is known for the fighting drama Warrior, the action thriller The Purge: Anarchy and the survival film The Grey. He later joined DC's screen universe as Rick Flag Sr., including the animated Creature Commandos.
How to watch his story
Watch The Winter Soldier, Civil War and Endgame in release order; his story makes sense only in that sequence. What If...? is optional and can be watched any time after Endgame, since its episodes are alternate takes on events you already know. If you only want his main arc, The Winter Soldier and the opening of Civil War are the two that count.