Plester's award-winning documentary Way of the Morris premiered at SXSW 2011 and received a limited theatrical release in UK cinemas before being released on DVD. Co-directed with Rob Curry and produced independently by Fifth Column Films, the feature-length documentary includes contributions from Billy Bragg, Fairport Convention's Chris Leslie and members of The Adderbury Village Morris Men. It was selected by the UK Film Focus as one of the "Breakthrough" British films of 2011. Plester and Curry are also responsible for the short field-recorded documentary Here We’m Be Together. Partly funded by a successful kickstarter campaign, the film also screened at the Rotterdam international film festival and in Denmark. Plester's writing credits for film include Ant Muzak, a short film directed by Ben Gregor and starring Nick Moran and Mackenzie Crook. It was the winner of an Audience Award at the 2003 Sydney Film Festival and was nominated for 'Best UK Short' at the 2003 Soho Rushes Festival and the 2002 Raindance Film Festival. He also wrote and created Blake's Junction 7 - again directed by Ben Gregor and starring Johnny Vegas, Mackenzie Crook, Mark Heap, Raquel Cassidy and Martin Freeman – which premiered at the 2004 Edinburgh Film Festival. Both films became cult hits and were released on DVD in 2008, along with a third film entitled World of Wrestling. Again created and written by Plester and directed by Gregor, the film stars Mackenzie Crook, Kevin Eldon, Patrick Baladi, Miranda Hart and Kris Marshall. In 2007, Plester also completed work on an offbeat romantic comedy entitled English Language - which marked his directorial debut. The short, in which Plester also starred, premiered at the 2007 Los Angeles Film Festival and went on to screen at over 45 film festivals worldwide, picking-up 5 awards along the way. He has also written and directed the JFK-inspired beat poemEt In Motorcadia Ego! and the award-winning 15-second film Slapphappy, which premiered at the Belfast Film Festival in 2008. Winner of the 1992/93 'National Student Playwright Of The Year' award, Plester has writing credits for the theatre including: Dakota ; Mad Dog Killer Leper Fiend ; and Yellow Longhair. Plester's many and varied acting credits for TV and film include: Lockout, Kick-Ass, Control, Cuban Fury, Closer to the Moon, Wolf Hall, Bone in the Throat, Shifty, Doctor Who, Life On Mars, Hustle, Murphy's Law, 1066: The Battle For Middle Earth, Magicians, It's All Gone Pete Tong, Galavant, Heist, Ant Muzak, Criminal Justice, Five Daughters, Silent Witness, The Wrong Mans, Uncle Dad, Goths, Residents, Poliakoff's Friends and Crocodiles, both series of Paul Whitehouse’s Happiness and the 2009 BAFTA-winning short film September. Plester played petty thief Linus Brody in the first two series’ of the BBC Birmingham production WPC 56. He played the role of Black Walder Rivers in the HBO series Game of Thrones and the homeless junkie Julian in After Life. In 2018, he played Roy Thomas Baker, Queen's producer, in the film Bohemian Rhapsody. In September 2019, he appeared in an episode of Doctors as Martin Taylor.