This introductory video shows what a murdle is and how to solve it. Murdles are whodunnit style puzzles by G. T Karber. His book Murdle vol. 1 features 100 unique murdles with increasing difficulty.
There is a problem of if you do many problems the same way, then in the future you are trained to solve problems in the same way so can be used to mislead you. Idk if this book will do that here, intentionally or unintentionally. Considering they assign a methodology to solving, it might be intentional.