*Frankie is a diesel engine who works at the Steelworks on the Mainland along with Hurricane.

Frankie is a charming and intelligent diesel shunter who can be very commanding. A natural leader, Frankie actively takes charge of operations at the Steelworks. She can be scheming at times, putting on a front to try and manipulate others into doing what she wants them to do.

Frankie, however, is not mean at heart. She feels hard-done-by and rejected because there is more work to do at the Steelworks than there are engines to do it. She would love to be free to go off making deliveries with Hurricane, but feels the only way she will ever be able to achieve this is by tricking others into doing the work she doesn't want to do.

Frankie is based on a Hudswell Clarke 0-6-0 diesel shunter which worked at the Manchester Ship Canal. No. 4002 Arundel Castle, affectionately known as "Billy", is preserved in working order by the East Lancashire Railway Diesel Group. Sister locomotive No. 4001 Alnwick Castle was also preserved as a static non-operational exhibit at the Winfields Store site at Rising Bridge before being broken up in early 2019. The American Diesels are also members of this class. No. 4002 is the number that Frankie carries in the special.

Frankie is painted blue-green and black with gold lining. She has red and gold nameplates on either sides and "M.S.C.", which stands for "Manchester Ship Canal", written above her face. The number "4002" is written in yellow on her front bufferbeam.*