Every other Friday, in a flat envelope that fits any letterbox: one big puzzle for the weekend and three small ones for the week.

Every puzzle comes with three sealed hints, each a little less subtle than the last. Open them in order, or hold out: the solutions arrive with the next pack.

Each pack starts gentle and ends tough. Most people crack the big one in an evening, alone or round a table with friends.

Yes, for up to three months, from your account page. Paused packs are never charged, and you can start again whenever you like.

Choose three, six or twelve packs and add a note. The first one goes out in a plain envelope, so the surprise holds.