Complex sentence: The character was an amalgam of his idea of an English gentleman; himself; and Fairlie: in literary terms, Drummond has his roots in Sherlock Holmes, Sexton Blake and Richard Hannay, although there is also an element of The Scarlet Pimpernel.
Split into simpler sentences: The character was an amalgam of himself, Fairlie, and his idea of an English gentleman. Drummond also had roots in the literary characters Sherlock Holmes, Sexton Blake and Richard Hannay, although there is also an element of The Scarlet Pimpernel.