The Third Doctor and Sarah arrive in 1970s London to find it has been evacuated because dinosaurs have appeared mysteriously. It turns out the dinosaurs are being brought to London via a time machine to further a plan to revert London to a pre-technological level.
| Directing | Paddy Russell | Director |
| Writing | Malcolm Hulke | Writer |
| Production | Barry Letts | Producer |
| Sound | Dudley Simpson | Music |
| Writing | Terrance Dicks | Script Editor |
| Writing | Robert Holmes | Script Editor |
