The Return of the Musketeers is a swashbuckling adventure film based on the characters created by Alexandre Dumas. It is a sequel to the 1973 film The Three Musketeers and the 1974 film The Four Musketeers.
Set in 1649, the film begins with Cardinal Mazarin, the chief minister of France, hiring the impoverished musketeer D'Artagnan to find his former companions, Athos, Porthos, and Aramis. Mazarin fears that the French people, inspired by the successful revolt against King Charles I in England, may rise up against the monarchy and he needs the musketeers to help maintain order.
D'Artagnan enlists Porthos, who is bored with his life of luxury, to help him track down the other musketeers. They find Athos, who is now a nobleman living with his intellectual son, and Aramis, who has become an abbé (a high-ranking member of the Catholic Church).
However, the musketeers are not on Mazarin's side. They are secretly working with the Duke of Beaufort, a popular leader who has been imprisoned by Mazarin for his political views. When Beaufort escapes from prison, the musketeers are blamed for his disappearance and are sent to England to rescue Charles I, who is being held captive by Oliver Cromwell.
In England, the musketeers encounter Charles's loyalists and Justine, the daughter of their old enemy, Milady de Winter. Justine seeks revenge on the musketeers for her mother's death, and she pursues them across the English countryside.
The musketeers manage to rescue Charles I, but they are unable to prevent his execution. They must then find a way to escape England and return to France, all while avoiding Justine and fulfilling their promise to help Beaufort's political reforms.
The film is a fun and exciting adventure that captures the spirit of the original novels. The cast, which includes Michael York, Oliver Reed, Frank Finlay, and Richard Chamberlain, are all excellent in their roles. Although not as well-known as its predecessors, The Return of the Musketeers is a worthy addition to the musketeer canon.