- "Come on mate! Let's give these bastards a proper British welcome!"
- — Wallcroft to Burns upon entering the Russian invaded Westminster Station.
Sergeant Wallcroft is a SAS soldier who served alongside Soap, Price, and Gaz during the events of Call of Duty 4: Modern Warfare and Call of Duty: Modern Warfare Remastered, primarily on the first two missions, "F.N.G." and "Crew Expendable". He later appears in Call of Duty: Modern Warfare 3 on the mission "Mind the Gap" alongside player-character Marcus Burns, and also appears in Call of Duty: Heroes. He is the Team Announcer of the SAS in the Multiplayer mode for Modern Warfare 3.
Cargo Ship Mission
- "Wallcroft's idea to switch to pistol vs. Reload - Pretty brilliant. Who knew Wallcroft could be
goodfast at anything?"
- — Soap on Wallcroft in Soap's Journal.
He appears in the mission "Crew Expendable" in Call of Duty 4: Modern Warfare and Call of Duty: Modern Warfare Remastered. Wallcroft, Griffen, and Gaz dropped down to the ship to retrieve a bomb headed to the Middle East after 'Soap' MacTavish and John Price cleared the first wave of Russian troops. Wallcroft and Griffen were ordered to cover Price's back while the rest went into the ship. Before Price and the others could retrieve the entire bomb, Baseplate reported a MiG airstrike on the way. Wallcroft and Griffen fled to the safety of the evac chopper. Price requested an update on their status and they reported that they were already in the chopper but told the four to get out just as the MiG's opened fire. The four managed to escape the ship and the chopper brought the group back to London. Wallcroft is also randomly generated in the mission All In.
Downtown London Mission
Wallcroft and Griffen reappear in the Call of Duty: Modern Warfare 3 campaign mission, "Mind the Gap", as an SAS squad leader. After the SAS picked up some suspicious cargo, the contents were not yet known. Baseplate assigned Wallcroft, Griffen and Marcus Burns and other SAS to intercept a group of 5 trucks with one of the crates carrying the unknown cargo. Marcus, Griffen and Wallcroft intercepted one of the trucks that was still at the docks, but it didn't have the cargo so Wallcroft, Griffen and Burns went into the subway where another truck was suspected of holding the contents. After avoiding other trains and civilians whilst chasing the train with a truck, the leading truck's driver was shot and killed, which caused the truck to crash and derail the train. Wallcroft and Burns survived but Griffen and the other SAS soldiers were killed in the crash. Wallcroft and Burns battled their way through the subway station, eventually meeting up with local police outside. Wallcroft and Burns met up with other SAS and police who had blocked off another road where another truck was suspected to pass through. Indeed, one showed up and the men opened fire on the truck, killing the drivers. They secured the truck and tried to contact Baseplate for a report on the other trucks were but received no response. Unfortunately, another truck exploded near the Palace of Westminster (Big Ben), killing a family, dozens of bystanders, and exposing the public to the deadly chemical. Wallcroft is later heard reporting that Downing Street is within the contamination radius.
Call of Duty: Heroes
He also appears in Call of Duty: Heroes as a Hero unit, unlocked after completing the Africa campaign.
Battle Aura: Reduce Enemy Accuracy by 4%.
Killstreaks: Smoke Grenade, Chaff Grenade, Drone Missile
- "Who dares wins." (Multiplayer when playing as the SAS at the start of a match)
- "Mission accomplished, good work." (Multiplayer when playing as the SAS when a match is won)
- "Didn't even break a sweat. Nice work." (Multiplayer when playing as the SAS when a match is won)
- "Good job squad." (Multiplayer when playing as the SAS when a match is won)
- "Suck it up, focus to the next battle." (Multiplayer when playing as the SAS when a match is lost.)
- "Mission failed, we'll get 'em next time." (Multiplayer when playing as the SAS when a match is lost)
- "Defeated. Don't let this happen again." (Multiplayer when playing as the SAS when a match is lost.)
- "We lost this round, but it's not over yet, get ready for the next one." (Multiplayer when playing as the SAS after losing a round of S&D)
- "Nice work, get ready for the next round" (Multiplayer when playing as the SAS after winning a round of S&D)
- "Pick it up, squad" (Multiplayer when playing as the SAS when losing a match)
- At the start of "Crew Expendable", in the helicopter, Wallcroft is not present. Only Price, Gaz, Griffen, a randomly generated SAS soldier, and the two pilots can be seen. However, he will instantly spawn opposite where the randomly generated SAS soldier was sitting (between Griffen and Gaz), once Soap, Price and the SAS soldier have rappelled down.
- In Mind the Gap, his character model may change after the train crash.
- If the player chooses to "skip the disturbing content" the decoy will explode but Wallcroft will continue standing unfazed in the explosion radius. This is interesting considering everyone else goes flying into the air as a result of the explosion.