2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/194330It is explicitly shown that part of the C-metric space-time inside the black hole horizon may be interpreted as the interaction region of two colliding plane waves with aligned linear polarization, provided the rotational coordinate is replaced by a linear one. This is a one-parameter generalization of the degenerate Ferrari-Ibanez solution in which the focussing singularity is a Cauchy horizon rather than a curvature singularity.6 pages. To appear in Classical and Quantum GravityGeneral Relativity and Quantum Cosmologytext