The castle appears at a key moment in the film; as love begins to blossom between the dysfunctional couple Maggie Smith and Timothy Bottoms, they wander among the historic ruins of the castle, where we are told by a tour guide that the Duque Infantado (of the Mendoza family) built it for his wife, although they never lived to enjoy it; setting the tone for Smith and Bottoms whose love is also unrequited, apart from some caravan sex.
Their tour of Spain is also dysfunctional, as it is Manzanares where they actually meet, according to the American cycle tour guide, and where Bottoms abandons his tour and jumps on Smith’s bus as it leaves the town, so why they should later, after a detour to El Escorial royal palace, return to Manzanares to visit the castle the following day, is unclear.
Love grows as they climb up the largely abandoned castle, ending up looking out of an ornate window across the Santillana reservoir.
He takes her to his castle, which he calls the castle of Aragón, and tries to seduce her with some typical noble past times such as whipping balloons.
They breakfast inside the castle, where a servant appears punctually from a hole in the ground every time the Duke blows his whistle, proving that servitude is alive and well in Spain.
The castle appears several times both before and after the meeting with the Duke.
Tim and Maggie wander through a market, set in the main square of Pedraza, which had previously been used as a different location for the first stop of the tour bus after Bottoms boards, and he buys her a dress, which she will wear to visit the Duke, provoking Bottoms’ jealous rage (again).
After leaving Pedraza, the castle and the Duke, they find resignation among the fountains of La Granja royal palace.