Understanding the cracking processes of rock is important regarding the fundamental material behavior and in engineering applications. Characterizing and predicting the cracking processes in shale is necessary when assessing unconventional oil and gas reservoirs and designing nuclear waste repositories. Of particular interest is the effect of bedding planes on the cracking processes. For this reason we tested one such shale, Opalinus shale, in this study. A series of unconfined compression tests were conducted on prismatic specimens with two pre-existing flaws and various bedding plane orientations. High speed- and high resolution imagery were used to capture crack initiation, -propagation and -coalescence between the flaw pairs and study the effects of bedding plane orientation and flaw pair geometry. It was found that in specimens with bedding planes aligned perpendicularly to the maximum applied compressive stress, the effects of the flaw angle and flaw pair bridging angle on the cracking processes were similar to those observed in previously tested rocks without bedding planes. However, as the bedding planes became more aligned with the direction of the maximum compressive stress the cracks initiating at the flaw tips propagated more frequently along the bedding planes. This visual observation is unique as previous studies did not characterize, in real-time, cracking along bedding planes (weak surfaces). Hence, the results from this study contribute to the understanding of cracking in anisotropic rocks.