Railway historian Tim Dunn and Siddy Holloway from the London Transport Museum explore hidden areas of the London Underground that—despite being just feet away from where millions of people regularly travel—hardly anyone knows about. The pair will explore abandoned tunnels, secret bunkers and hidden staircases that have been concealed from public view for years.
| Title | Air Date | Duration | ||
|---|---|---|---|---|
| Season 1 | Episode 1 | Holborn | 2021-07-19 | 60 min |
| Season 1 | Episode 2 | North End | 2021-07-26 | 60 min |
| Season 1 | Episode 3 | Piccadilly Circus | 2021-08-02 | 60 min |
| Season 1 | Episode 4 | Euston and York Road | 2021-08-09 | 60 min |
| Season 1 | Episode 5 | St Mary's, Aldgate East and Oxford Circus | 2021-08-16 | 60 min |
| Season 1 | Episode 6 | Clapham South and Moorgate | 2021-08-23 | 60 min |
| Season 2 | Episode 1 | Charing Cross and Kennington | 2022-05-05 | 60 min |
| Season 2 | Episode 2 | Waterloo & City | 2022-05-12 | 60 min |
| Season 2 | Episode 3 | King William Street and Knightsbridge | 2022-05-19 | 60 min |
| Season 2 | Episode 4 | Brompton Road and St Pauls | 2022-05-26 | 60 min |
| Season 2 | Episode 5 | London Bridge and Ongar | 2022-06-02 | 60 min |
| Season 2 | Episode 6 | King's Cross and Marlborough Road | 2022-06-09 | 60 min |
| Season 2 | Episode 7 | Elizabeth Line and Angel | 2022-06-16 | 60 min |
| Season 2 | Episode 8 | Quainton Road and Kingsway | 2022-06-23 | 60 min |
| Season 2 | Episode 9 | Greenwich and Notting Hill | 2022-06-30 | 60 min |
| Season 2 | Episode 10 | Baker Street and Edgware Road | 2022-07-07 | 60 min |
| Season 3 | Episode 1 | Camden | 2023-07-04 | 60 min |
| Season 3 | Episode 2 | South Kensington and Marylebone | 2023-07-11 | 60 min |
| Season 3 | Episode 3 | Green Park (Dover Street) and Down Street | 2023-07-18 | 60 min |
| Season 3 | Episode 4 | British Museum and Leinster Gardens | 2023-07-25 | 60 min |
| Season 3 | Episode 5 | West Ashfield & Oval | 2023-08-01 | 60 min |
| Season 3 | Episode 6 | Leicester Square and Hyde Park Corner | 2023-08-08 | 60 min |
| Season 3 | Episode 7 | Heathrow and Swiss Cottage | 2023-08-15 | 60 min |
| Season 3 | Episode 8 | Shepherd's Bush | 2023-08-22 | 60 min |
| Season 3 | Episode 9 | Acton Works | 2023-08-29 | 60 min |
| Season 3 | Episode 10 | Archway and Emergency Response Unit | 2023-09-05 | 60 min |
| Season 4 | Episode 1 | Earl's Court | 2024-07-02 | 60 min |
| Season 4 | Episode 2 | Paddington | 2024-07-09 | 60 min |
| Season 4 | Episode 3 | Waterloo and Marble Arch | 2024-07-16 | 60 min |
| Season 4 | Episode 4 | South Kentish Town | 2024-07-23 | 60 min |
| Season 4 | Episode 5 | Thames Tunnel and Lambeth North Street | 2024-07-30 | 60 min |
| Season 4 | Episode 6 | Ruislip Depot and Warren Street | 2024-08-06 | 60 min |
| Season 4 | Episode 7 | Northumberland Park and Finsbury Park | 2024-08-13 | 60 min |
| Season 4 | Episode 8 | Stockwell and the DLR | 2024-08-20 | 60 min |
| Season 4 | Episode 9 | Gloucester Road | 2024-08-27 | 60 min |
| Season 4 | Episode 10 | Old Street | 2024-09-03 | 60 min |
