Martin is a British professional racing driver, who won the FIA World Endurance Championship LMP2 title in 2013 and has also competed in IndyCar and the American Le Mans Series. He is a GT4 Champion in British GT alongside fellow ambassador Kelvin Fletcher.
After several extremely successful years in karting, Toyota signed Plowman to a 10-year contract to their young driver program. He made his professional debut in 2006 driving in Italian Formula Renault for Prema Powerteam, finishing 5th in the Italian Series, claiming rookie of the year.
He returned to the same team and series in 2007, finishing joint 7th with Team-Mate Henkie Waldscmidt in Italian Formula Renault. A disappointing end to the campaign for the Prema Powerteam after holding 1–2 in the championship halfway through the season. Plowman was dropped from the Toyota young driver program at the end of 2007.
In 2008 Plowman became an official Volkswagen junior driver where he was assigned to the newly re-formed RC Motorsport team and drove in the first seven rounds (14 races) of the Formula Three Euroseries where he failed to score any points and only managed a best finish of 17th. He also drove in the Masters of Formula 3 with Signature-Plus where he finished 14th.