False Alarm, Harold's Bad Day, Henry's Dizzy Day, Surprise, Surprise!, Mountain Rescue, Queen of the Road!, Super Heroes! ( does not speak), Flying Fish! ( cameo), Broken Bridges ( cameo), Cruise Control! ( does not speak), Really Fast Food!, Percy the Post!, Happy and Sad ( cameo), Air Share! and Animals ( does not speak)

Henry Gets It Wrong! ( does not speak), Harold Afloat, Misty Island Rescue ( cameo), Saving Santa!, Thomas Takes Off!, Thomas and the Rainbow! ( does not speak), In a Spin and Disgusted Diesels ( cameo)The Thomas Way ( does not speak), Kite Flying ( does not speak), William's Wish, Edward the Helpful Engine ( mentioned) and Not Now, Charlie! ( does not speak) Harold flew by at Tidmouth Sheds for a routine flyby and greeted the steam engines, accidentally spreading sneezing powder all over Thomas, Splatter and Dodge, dumped by Diesel 10. In earlier scripts, he did not speak and he spread quarry dust in the quarry bowl all over the three engines. Top 5 Non-Railway Vehicles ( does not speak), Thomas the Helicopter and Thomas and the Birthday Surprise Series 14 - Henry's Health and Safety ( cameo), Being Percy ( cameo), Jumping Jobi Wood! ( does not speak), Jitters and Japes ( cameo) and Merry Misty Island

Series 7 - Five New Engines in the Shed, There Once Was an Engine Who Ran Away and The Whistle SongHarold also speaks in a manner reminiscent of an RAF pilot, using terms such as "wizard" and "old chap" in conversation.

The fifteenth series episode, Stop That Bus! was the first time Harold has flown outside of The Island of Sodor. Harold also appeared in the magazine stories, Bright Sight, Company for Cranky, Fishy Diesel!, Harold and the Broken Tree, Lost Luggage!, On Inspection, Ride and Slide, Sky High!, Smoke Signals, Smoky Sky, Steaming Along!, Stone Signal, The Best Band, The Great Air Race and The Great Statue Robbery.The Eyesight Test ( mentioned), A Special Story About Harold, The Kite Contest, Harold Goes Quiet, Airborne Engine and Eye-in-the-Sky When Harold first met Percy, he stated that railways were "slow and out-of-date", but was proven wrong when Percy beat him in a race. Harold also dropped hot drinks for Percy's crew when they were stranded in a flood. Mine Mystery ( cameo), Tidy-Up Time! ( cameo), A Treat for Trying ( cameo), Tunnel Trouble and Naughty or Nice? Series 7 - Emily's New Coaches ( cameo), Harold and the Flying Horse, The Grand Opening ( does not speak), Best Dressed Engine ( cameo) and Three Cheers for Thomas Harold's theme in the second series is a musical variation on the main score of the 1955 film, The Dam Busters.

TOOT-TOOT HELICOPTER: This cute and colourful Helicopter toy will entertain your child for hours on end with its light-up face button that triggers fun music, realistic sound effects and sing-along songs. Press the feature button or push the toy around for even more excitement. However, he still had a bit of a rivalry with Percy. Once, when the Mail Train was threatened to be scrapped, rumours began to spread that Harold would make the deliveries instead. However, Thomas and Percy worked even harder than ever to prevent that from happening and Harold's chances of taking over the mail run were stopped when the unpredictable strong winds caused him to be grounded. They're based in convenient locations including supermarkets, newsagents and train stations. Plus they're often open late and on Sundays. IDEAL GIFT FOR CHILDREN: This baby music toy is the perfect Christmas gift, birthday or Easter present for babies and toddlers to develop auditory and tactile skills while enjoying hours of learning fun with all their favourite Toot-Toot Drivers. Harold was the only character introduced after the first series to have a speaking role in Thomas and the Magic Railroad.ENCOURAGE CREATIVE PLAY: These cute toddler toys are great for developing motor skills, showing cause and effect and encouraging role play as children push buttons and drive them around, triggering fun sounds, melodies and lights, and use their imagination to bring their new Drivers friend to life. Quotes " Hello", said Percy, " Who are you?" " I'm Harold. Who are you?" " I'm Percy. What whirley great arms you've got!" " They're nice arms!" said Harold, offended. " I can hover like a bird. Don't you wish you could hover?" " Certainly not! I like my rails, thank you". " I think railways are slow!" said Harold in a bored voice. " They're not much use and quite out of date". Series 2 - Percy and Harold, The Runaway and Thomas and the Missing Christmas Tree ( does not speak)