This paper examines the key features of the transmission and reflection spectra of a one-dimensional photonic crystal structure in which a nanocomposite layer is sandwiched between dielectric Bragg mirrors. Two orthogonal polarisations of an incident wave correspond to different plasmon resonance frequencies of the nanocomposite. If one of the plasmon frequencies coincides with the defect mode frequency in one of the photonic bandgaps, complete suppression of the defect mode in the transmission spectrum is possible, which makes the spectra of such structures polarisation-sensitive.