S9E11
Cynical with flashes of pragmatic hope
Written by Malcolm Hulke
View Graph

The Sea Devils Part 3

The Doctor and Jo Grant must evade the Master and Colonel Trenchard's forces while uncovering a sinister plot to resurrect an ancient evil, all as the Master manipulates Trenchard to further his reptilian allies' return to power.

In 'The Sea Devils - Episode Three', the Doctor and Jo Grant find themselves entangled in a complex web of deceit and danger on a remote island. The Master, a renegade Time Lord, has escaped and is manipulating Colonel Trenchard, using him to further his own ambitions. The Master's goal is to contact an ancient race of reptilian beings who once ruled Earth and help them reclaim their former dominance.

The episode begins with the Doctor and Jo investigating the Master's activities at a naval base. However, their efforts are quickly thwarted when the Master orchestrates events to have the Doctor arrested and imprisoned. Jo manages to escape and sets out to rescue the Doctor, navigating through the castle's hidden passages and eventually freeing him from his cell.

Meanwhile, Colonel Trenchard, under the Master's influence, becomes increasingly paranoid and isolated. He orders his guards to capture Jo and prevent her from rejoining the Doctor. The Master uses Trenchard's resources to build a device that will lure in and trap the Doctor and Jo, as well as UNIT personnel who are searching for them.

As the Doctor and Jo attempt to evade capture, they discover that the island is surrounded by a mysterious entity known as the 'sea devils'. A submarine, commanded by Captain Hart, is sent to investigate strange occurrences at sea, which may be connected to the Master's plan.

The episode culminates with the Doctor and Jo making a daring escape, the Master's device being activated to trap the UNIT personnel and the 'sea devils' being revealed as an ancient, aquatic threat to humanity. The Doctor must once again outwit the Master and prevent a catastrophic outcome.


Events in This Episode

The narrative beats that drive the story

38
Act 1

The episode commences with the Master's calculated manipulation of Colonel Trenchard, orchestrating the Doctor's arrest on fabricated charges of attacking a government employee and a prisoner. This immediate incarceration sets the Doctor's primary objective: to expose the Master's deceit and escape Trenchard's misguided authority. Concurrently, Jo Grant, initially attempting to leave the naval base, deftly evades capture by Trenchard's guards, pivoting her focus entirely to rescuing the Doctor. Her escape establishes a parallel narrative of infiltration and liberation. Meanwhile, a critical subplot unfolds as Captain Hart dispatches Commander Ridgeway's submarine to investigate an alarming series of disappearances at sea, explicitly mentioning the mysterious "sea devils," thus introducing the overarching aquatic threat. The act culminates in a pivotal confrontation in the Master's cell, where he brazenly reveals his true, sinister ambition to the manacled Doctor: to contact and empower an ancient, reptilian race, the former rulers of Earth, to reclaim their dominance and exterminate humanity. This declaration solidifies the core conflict and the immense stakes involved, driving the narrative forward with a clear antagonist goal.

Act 2

Following the Master's chilling revelation, Jo Grant intensifies her efforts to free the Doctor, embarking on a determined infiltration of the heavily fortified castle. She meticulously navigates its hidden passages, scouting for an entry point and eventually locating the Doctor's cell. Her persistent actions underscore the urgency of their situation and her unwavering loyalty. Simultaneously, Captain Hart at the naval base grows increasingly suspicious of Colonel Trenchard's vague and contradictory explanations regarding the Doctor and Jo's sudden disappearance. Trenchard, still under the Master's sway, attempts to maintain his façade by using a monitor to show Hart a fabricated image of the Master, posing as the Doctor, thereby temporarily deflecting suspicion. Concurrently, Commander Ridgeway's submarine, tasked with investigating the "sea devils," experiences a catastrophic encounter underwater. Its sonar system fails spectacularly, leading to a complete loss of power and the vessel sinking helplessly to the seabed, confirming the immediate and tangible threat of the mysterious entities. Back in the castle, Jo successfully establishes contact with the Doctor, devising a coordinated escape plan. She then skillfully picks the lock on his manacles, physically liberating him from his confinement and setting the stage for their imminent flight.

Act 3

The act ignites with the Doctor and Jo's dramatic escape from the Master's cell, where they swiftly overpower their guard and make their break. Colonel Trenchard, upon discovering their absence, reacts with furious urgency, immediately mobilizing every available guard and declaring the Doctor and Jo "dangerous enemy agents" in a desperate attempt to recapture them. This heightened pursuit escalates the stakes significantly. Concurrently, the stranded submarine, now resting on the seabed, endures a violent and terrifying assault. Unseen forces, unequivocally identified as the "sea devils," breach the vessel's hull, confirming their aggressive nature and the grave danger they pose. The Doctor and Jo, in their frantic flight, race towards the island's beach, unknowingly running directly into a meticulously prepared trap. The Master, having completed his sophisticated device, activates it, broadcasting a powerful signal designed to lure and ensnare not only the escaping Doctor and Jo but also any UNIT personnel who might be searching for them. This final action culminates the immediate narrative, setting a perilous stage for the unfolding conflict and the full revelation of the sea devils' power.