In the novel Evil Under the Sun, Odell C. Gardener is the husband of Carrie Gardener, a couple from New York holidaying at the Jolly Roger Hotel. Devoted to his garrulous wife, he spent most of his time fetching things for her and agreeing with her when asked to do so. Nonetheless Poirot credited him as a sensible man and sought his opinion about the various guests at the hotel, particularly about Arlena Marshall.
Mr Gardener has "shrewd grey eyes", and speaks with a slow drawl. According to Poirot, Mr Gardener plays tennis and golf, and "has a form of dry humour that is attractive when one gets him to oneself".
On the morning of the murder, Mr Gardener is on the beach with his wife. At one point, she sends him back to the hotel to fetch a skein of purple wool for her knitting. Later that day, he plays tennis with Christine Redfern, Rosamund Darnley, and Captain Marshall.
Poirot reveals at the end of the novel that he knew that Miss Darnley had lied about returning to the hotel and seeing Captain Marshall in his room, as Mr Gardener had returned to the hotel to fetch the skein of wool at about that time, and had not seen her.
Evil Under the Sun (1982)
In the 1982 Ustinov adaptation, Odell Gardener has a slightly different backstory. Again, like the changes to the other characters in this adaptation, he also knows Arlena Marshall. Here he and his wife Myra are theatrical producers from New York. They had at one time put up a play but Arlena had walked off the production with a doctor's certificate (which the Gardeners believe to be fake). Now they are producing another play and really need Arlena to star in it. For Poirot, Odell becomes a plausible suspect by elimination simply because he could not produce an alibi for the time Arlena was killed. However, without him knowing about it, Daphne Castle later alibied him because she had seen him in the hotel garden while she was conducting a staff meeting.
Odell Gardener is portrayed by James Mason.