Bill or Ben?

"Oh, dear. What's happened here, sir?" "Oh, no. Has Connor broken down, sir?" "There are two of you! You played a trick on me. You aren't really faster than I am!"

- Bill, Ben, and Connor

Bill or Ben? is the fifteenth episode of the seventeenth series.

Plot
One day, a big and fast engine Bill and Ben have never seen before pulls onto their track at a junction while puffing along the main line. Further along the line, Bill and Ben meet Thomas, who tells them that the streamlined engine was Connor. The twins think that Connor must be full of himself because he races around and surprises other engines. Thomas tries to explain that Connor is friendly, but the twins are not convinced.

Sometime later, the twins pass through Henry's tunnel when they get surprised by Connor again. Ben is still inside the tunnel as Connor passes and whistles hello to Bill. The twins decide to play a trick on the streamlined engine.

The next time Connor comes to Sodor, Bill is waiting for him. Bill challenges Connor to a race, but the big streamlined engine does not think it would be fair to race against such a small tank engine. Eventually, Connor agrees and when the signal turns green, they both race off towards Ulfstead Castle. Bill is soon left far behind and Connor thinks he has won. Connor gets a massive shock when he pulls into Ulfstead Castle and sees Ben waiting at the platform. Connor falls for the twins' plan and thinks it is Bill who has beaten him to the castle. Ben suggests that they have a rematch and race back to the bridge. Connor agrees and the race soon starts.

This time, Connor takes no chances and only focuses on beating the little tank engine. He concentrates on the race so hard that he runs through a red signal and nearly causes a serious accident with Henry. Connor's relief is short-lived as the Fat Controller pulls up in Winston who saw the almost incident. He is very cross with Connor for missing the red signal as safety comes first. Connor promises not to do it again. Just then, the twins both pull up and Connor realises that he was being tricked all along. The Fat Controller is not amused with Bill and Ben's antics and punishes them by ordering Bill to be repainted so that they cannot be confused so easily.

At the Sodor Steamworks, Bill tries to get out of being repainted but Victor has been warned in advance by the Fat Controller about the twins' tricky ways. Shortly, Bill has a brand new dark blue livery.

Back at the shunting yard, Ben laughs when he sees his twin. Bill is not happy; now that he does not look the same as his twin, it is no fun at all. Then, Ben has a crafty idea and heads off to the Steamworks himself. When he arrives, Victor is not there and Ben tells Kevin that he is Bill and has come to be repainted in accordance with the Fat Controller's orders. Kevin is unsure as he thinks Bill was repainted the day before, and thinks that he should wait until Victor returns so they can arrange it, but Ben refuses to wait, and threatens to involve the Fat Controller. Kevin, not wanting to get into trouble with the Fat Controller, agrees to let Ben be repainted. Soon, Ben has been painted the same colour as Bill. Victor arrives and is not happy, but there is nothing he can do; the job has already been done.

Bill and Ben, now both painted dark blue, are on their way again when they see Connor up ahead. The twins decide to play another trick on him. Bill challenges Connor to another race. Connor agrees, thinking aloud about his assurance that only one of the twins has been repainted. Connor thinks he will definitely win, but Bill is not so sure...

Characters

 * Thomas
 * Henry
 * Bill and Ben
 * Connor
 * Victor
 * Kevin
 * Sir Topham Hatt
 * Rosie
 * Winston
 * Troublesome Trucks
 * The Teacher
 * The Bird Watcher
 * One of Dowager Hatt's Friends
 * The Lady with the Big Hat
 * The Welsh Bird Watcher
 * The Great Railway Show Judge

Locations

 * Island of Sodor
 * Knapford Yards
 * Ulfstead Castle
 * Sodor Steamworks
 * Victor's Shed
 * Henry's Tunnel
 * Vicarstown Bridge
 * The Mainland

UK

 * Ben Small as Thomas
 * David Bedella as Victor
 * Jonathan Broadbent as Bill and Ben
 * Jonathan Forbes as Connor
 * Keith Wickham as Henry and the Fat Controller
 * Matt Wilkinson as Kevin

US

 * Martin Sherman as Thomas
 * David Bedella as Victor
 * Jonathan Broadbent as Bill and Ben
 * Jonathan Forbes as Connor
 * Kerry Shale as Henry, Kevin and Sir Topham Hatt

Trivia

 * Going by production order, this is the twenty-fourth episode of the seventeenth series.
 * This episode is very similar to the magazine story Diesel's Race (which was also written by Andrew Brenner). It also has similarities to the second series episode, The Diseasel.
 * This episode marks the first of two things:
 * The first time since the seventh series episode, Bill, Ben and Fergus that Bill and Ben have had leading roles in an episode.
 * The first time since the film, Thomas and the Magic Railroad where all of the engines have lamps.
 * Connor's close call with almost colliding with Henry is an example of performing a real-life railway danger known as a SPAD (Signal Passed At Danger).
 * This is the third episode to use a question mark in the title, the second being Which Way Now?, and the first being What's the Matter with Henry?.
 * In the Estonian, Latvian, Lithuanian, Baltic Russian and one of the Vietnamese dubs, the UK dub can be heard in the background as a dubbing track was not used.

Goofs

 * Henry's brake van changes between shots.
 * When Connor screeches to a stop, his bogie wheels and trailing wheels spark, but neither are fitted with brakes.
 * Through out the episode, small parts of Connor's driving rods are not connected to his wheels and do not move.
 * When Bill and Ben speak to Thomas, Ben is not coupled to the trucks.
 * When Connor nearly hits Henry's train, the initial shot of him shutting his eyes as he applies his brakes shows him slowing down inches from Henry. In the next shot, Connor is not even at the points yet.
 * When Connor realises that he had been tricked, his valve gear is not connected to his crosshead.

Merchandise

 * Wooden Railway
 * Capsule Plarail
 * Magazine stories - Bill or Ben

Home Media Releases
{{Scroll box|

UK

 * Railway Mischief
 * 1st Class Stories
 * The Complete Series 17

DVD Boxsets

 * 10 DVD Boxset

US

 * Engines to the Rescue
 * Season 17

DVD Boxsets

 * Engines to the Rescue and Tale of the Brave Double Pack

AUS

 * Railway Mischief

GER

 * Thomas' Snowplough

HRV

 * Phantom Express

MYS

 * The Thomas Way

JPN

 * Thomas the Tank Engine Series 17 Vol.2

THA/CHN
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 * No Snow For Thomas

¿Bill o Ben? ביל או בן? Wiluś czy Benio? Билл или Бен?