While not being responsible for the death of Maggie Buckley, this man is the one resposible for Freddie Rice's condition and her drug addiction due to his abuse, thus is indirectly involved in the culprit's plan with the coccaine supplied to them and Freddie.
While not having a significant role within the story, the husband of Freddie was revealed to be a domestic abuser, who was seperated from his wife long ago. While suffering from a serious disease and was dying, he kept sending notes and demanded his wife to send money to him. Freddie had developed her coccaine addiction to get rid of the annoyance of which her husband brought.
Nevertheless, during Poirot's denouement, Freddie's husband arrived at End House in an attempt to murder his wife. He fired a shot at Freddie from the window, but was missed. The man was soon arrested when Poirot declared this man as his originally theorized "tenth suspect" of murderer on his list, which was originally referring someone who was never presented in the crime scene publically at all. The arrest of Freddie's husband was soon followed by the arrest of Nick Buckley, whom Poirot had declared to be the hidden "eleventh" suspect and the true mastermind behind Maggie's murder.
It is most likely that Freddie's husband would die in prison due to his condition. After the case's closure, Poirot managed to pair Freddie with Jim Lazarus, who was in love with her since the beginning, in order to cure Freddie from her drug addiction.
- In Agatha Christie's Poirot, Freddie's husband was omitted. The denouement ended with George Challenger's arrest and did not uncover the true reason behind Freddie's drug addiction. In addition, it became unknown whether Freddie and Jim became couples like that in the novel.