Deadly Nightshade

Slow even at 58 minutes, Deadly Nightshade stars Emrys Jones, Zena Marshall, and Joan HIckson.

Jones has a dual role, one as an escaping prisoner, Barlow, and the other as a man named Matthews mistaken for him and arrested, later released.

While the police are looking for Barlow, he finds his double, whose arrest was publicized. A fight ensues, and Mathews is killed accidentally. Barlow hides the body and assumes Matthews' identity.

You can tell one of the things that's going to give him away immediately, but overall, he doesn't seem to be very confident in his disguise. Complications arise when a ship blows up and some of the survivors have to be put up in different homes for the night. One of them is Barlow's old girlfriend (Zena Marshall).

The big problem is that with the ID switch, Barlow has gone from the frying pan into a very hot fire.

I wasn't familiar with Emrys Jones; Zena Marshall was a Bond girl. Joan Hickson, Miss Marple to many of us, plays Matthews' maid.