| JJohn HaslerThomas (voice) | Thomas (voice) |
 Keith WickhamEdward / Gordon / Harvey / Salty / Harold / The Fat Controller / Glynn / Various (voice) | Edward / Gordon / Harvey / Salty / Harold / The Fat Controller / Glynn / Various (voice) |
 Rob RackstrawJames / Toby / Bernie / Professor Friedrich (voice) | James / Toby / Bernie / Professor Friedrich (voice) |
 Nigel PilkingtonPercy (voice) | Percy (voice) |
 Teresa GallagherEmily / Annie / Clarabel (voice) | Emily / Annie / Clarabel (voice) |
 Nicola StapletonRosie (voice) | Rosie (voice) |
| YYvonne GrundyNia (voice) | Nia (voice) |
 Rachael Louise MillerRebecca / Dr. Hetty (voice) | Rebecca / Dr. Hetty (voice) |
 Joe SwashSonny (voice) | Sonny (voice) |
| MMatt WilkinsonCranky (voice) | Cranky (voice) |
 Mike GradySir Robert Norramby (voice) | Sir Robert Norramby (voice) |
 Dominique MooreRuth (voice) | Ruth (voice) |
| BBob GoldingBaz (voice) | Baz (voice) |
 Matt McCooeyKenji (voice) | Kenji (voice) |
 Colin McFarlaneDr. Holyfield (voice) | Dr. Holyfield (voice) |
| SSiu-see HungDr. Kim (voice) | Dr. Kim (voice) |
 Kerry ShaleDiesel (voice) | Diesel (voice) |
 Togo IgawaHiro (voice) | Hiro (voice) |
 David BedellaVictor (voice) | Victor (voice) |
 Tim WhitnallReg (voice) | Reg (voice) |
| LLaura BeaumontFair Attendees (voice) (uncredited) | Fair Attendees (voice) (uncredited) |
| PPaul LarsonFair Attendees (voice) (uncredited) | Fair Attendees (voice) (uncredited) |
| IIan McCueFair Attendees (voice) (uncredited) | Fair Attendees (voice) (uncredited) |
| SSharon MillerFair Attendees (voice) (uncredited) | Fair Attendees (voice) (uncredited) |
| ZZahara AndrewsFair Attendees (voice) (uncredited) | Fair Attendees (voice) (uncredited) |
