Len was a Perivale resident who worked in a grocery shop with Harvey. The Seventh Doctor visited their shop to buy cat food. Len followed the Doctor out to the sidewalk when the Doctor exited without paying for the bundle of cat food he was carrying.
After the Doctor left, Len was called to the back by Harvey who discovered that something had attacked and killed their cat. (TV: Survival)
Behind the scenes
Len's co-worker Harvey's was portrayed by Gareth Hale's long-time friend and comic partner Norman Pace. The grocery shop scene was, in effect, a Pace & Hale joint appearance.