| Sally Hawkins | Eliza Esposito | |
| Richard Jenkins | Giles | |
| Michael Stuhlbarg | Mr. Robert Hoffstetler | |
| David Hewlett | Fleming | |
| Stewart Arnott | Bernard | |
| Lauren Lee Smith | Elaine Strickland |
| Michael Shannon | Strickland | |
| Octavia Spencer | Zelda | |
| Doug Jones | Amphibian Man | |
| Nick Searcy | General Hoyt | |
| Nigel Bennett | Mihalkov | |
| Martin Roach | Brewster Fuller |