He was voiced by Joe Mantegna, who also played Fat Tony from The Simpsons.
In the movie Grem first appeared on the oil deck and as one of the Lemons who had thought to have killed Finn McMissile. He was next seen in Japan when he along with Acer attacked Rod Torque Redline in the bathroom. Rod then managed to pass along information to Mater(who happened to be there) regarding the conspiracy plot. Afterwards, Grem killed Rod who was being pumped with Allinol with the electromagnetic pulse camera that would be used to blowout the race cars during the world Grand Prix as demonstrated by Professor Z. Grem was assigned to use the camera on the race cars during the world Grand Prix. He aimed the camera beam at a racer and with the result of the Allinol heating up, blew out their engine. Grem and Acer also caused a big crash in Italy. After Mater, Finn and Holley tried to stop the lemons, they were all captured. Grem was then assigned to kill McQueen using the camera but since Sarge and Fillmore switched out the Allinol with Fillmore's organic biofuel mixture, the camera beam didn't work. When Mater discovered the bomb strapped to his radiator and McQueen chased Mater down to see what the situation was, Grem along with Acer persutied them throughout London until Holley Shiftwell intervened and threw Grem and Acer off the road and into a bar where to two lemons were beat up by the bigger and tougher cars residing there. Grem along with Acer and the other lemons were presumably arrested soon after.