Trawling through the box, which contained figures from 1980s, the 35-year-old discovered a small square packet - which turned out to be a 30-year-old He-Man jelly sweet, which had never been unwrapped from its packaging.
Gavin, who lives in Ditherington, Shrewsbury, said: "I have been collecting figures since I was small. My dad bought me my first one, which was a He-Man figure and since then I have been collecting them. I collect He-man, GI Joe and Transformers and I live with my sister and she tolerates them.
"Any children I know are allowed to look at them from a distance but they aren't allowed to touch then and certainly not allowed to play with them. I suppose I buy a few a month. The collection is pretty big now and is something I will continue to do."
Gavin was browsing in a specialist retro shop in Shrewsbury when he spotted the non-descript box of action figures.
"I was just having a look around a shop in Shrewsbury when I saw a box full of action figures," said Gavin. "I asked how much they wanted for the box and paid £5. It was only when I got home that I had a good look through and found the jelly sweet at the bottom.
"I don't think its is worth very much but the fact that it is 30 years old and hasn't been opened is quite interesting. I have had a look on the internet but haven't found one for sale. I certainly won't be eating it."
And while the sweet may not be valuable, some action toys sell for thousands of pounds, if in their original packaging.