In a series of papers Amati, Ciafaloni and Veneziano and 't Hooft conjectured
that black holes occur in the collision of two light particles at planckian
energies. In this talk based on \cite {AVV} we discuss a possible scenario for
such a process by using the Chandrasekhar-Ferrari-Xanthopoulos duality between
the Kerr black hole solution and colliding plane gravitational waves.Comment: Cont.Proc. of VI Quantum Gravity Seminar, 15 pages, LATE