Strange Lightning Style Experience

Here is one of the few stange experiences I have had in my life:

I was sat in the living room watching TV and the wife was in the kitchen behind the living room, separated by a wall.

Through the small gap between the curtains came three flashes in succession separated by a noise similar to a camera flash charging. I would guess there was a quarter to half second gap between the flashes.

You could explain this easily apart from the blue lightening style effect that travelled through the living room, through the door into the kitchen / dining room and out through the french doors. I ran to the window to see if someone was there (nope) then through to ask the wife if she saw anything and she said she saw a blue flash go through the back doors.

There wasn't any storms around on this evening. The "flash charging" noise was very loud compared to a normal flash and was more of a "pingy" noise. I wouldnt have heard a normal flash through the double glazing.

Anyone had similar or an explanation?