Anthony Gilbert 
The Body on the Beam [EPUB ebook] 

Suicide – or murder? The tiniest clue holds the answer. Classic crime from one of the greats of the Detection Club When Florence Penny’s body is found hanging from a beam in the bedsit she has been renting, it looks to Inspector Field like a case of suicide. Soon, though, he realises murder is the motive, and the discovery of a single pink bead among the disordered bedclothes leads him to prime suspect Charles Hobart. It’s now up to Scott Egerton, Hobart’s prospective brother-in-law, and an astute private inquiry agent named Gordon to establish Hobart’s innocence . . .