- "Looks like the last of the Huns, eh Davis?"
- — MacGregor on meeting John Davis
MacGregor served in El Alamein, Toujane, Matmata, and Caen alongside Captain Price and Sergeant John Davis. On one occasion, he served as the radio operator. Price also trusted MacGregor with driving, despite nearly getting Davis killed. Davis has saved MacGregor's life numerous times, since one can hear him say, "Good work Davis, I owe you one! Hell I owe you two!"
MacGregor is first seen at El Alamein with Price when Davis and his squad catch up with them. When the German camp was ravaged, Price ordered Davis to collect enemy plans. MacGregor, who is a hothead, said, "We don't have time to collect a lot of stupid maps!" Price denied him, saying, "Keep your bloody mouth shut, Private!" Later, MacGregor and Davis worked together calling in artillery on a German ambush.
At Toujane, Price, Davis, and MacGregor became trapped in a building by Germans. They took an armored car through Toujane, escaping death by enemy infantry, Panzerschrecks, and a tank. MacGregor drove over mines that threw Davis out of the turret. They managed to escape the city and later met up again during the next attack. When the Germans were defeated he stated, "Looks like the last of the Huns, eh Davis?"
MacGregor is by Price's side at Matmata and again in Caen. When the British soldiers found wounded American POWs, MacGregor and Davis were sent to steal a German transport. MacGregor drove the vehicle again through heavy resistance, and nearly got himself killed again. He was last seen at the last British mission, The Brigade Box. It is later revealed that he lived through the war.